Hello,
I just got my new Xperia Z having used my ancient Iphone 1G for the last 4 years and I have no experience with Android and anything related to it what so ever. I've spent the last 2 days tirelessly working my way through various forums, guides, wikis to get an idea what I'm dealing with here and where to start, but there's an important decision that I could really use your thoughts and tips on.
After reading up on it, I decided I want to root my phone and this seems to be somehow connected to unlocking the bootloader and this is where I'm worried. I read the guide on how to unlock the bootloader and the warning about losing DRM Keys and the consequences of this scared me away from it. Now I'm left wondering, and this is my actual question here:
What is the difference between unlocking the bootloader and rooting my phone and simply rooting without unlocking the bootloader?
And in case the things I want to do are only available with an unlocked bootloader: how damaging is it to lose DRM keys and therefore the bravia engine and gracenote? What made you decided for or against unlocking the bootloader?
Thanks!
Hi,
maybe I can help you.
Bootloader is like the BIOS of a PC. It checks everything at start up.
Locked Bootloader only allows to run the Stock FW and in this case the DRM-Keys are working (everything is checked and safe)
Unlock the Bootloader means you were able to install an modified / other FW and then you loose the DRM-Keys (the manufacturer hasn´t checked the FW and it is in the eyes of an manufacturer "not safe". You will also loose your warranty.
If you unlock the bootloader Root is always possible as I know.
In this case the system is not from the manufacturer and unofficial modification could be done to the system. Normally all modified Systems have Root access. So you were able to do things that the manufacturer has normally not allowed. Modify system files or something like that. Also it could be possible to copy for example a downloaded and payed movie to another device. This is why you were not able to download a movie on the Play Store if you have root. On a locked bootloader the FW (system) does not give you the possibility to copy the movie to an other device and everything is "safe" (from the view of companies). No illegal copies are possible. (DRM-Keys)
Since some days Root is also possible on a locked bootloader.
The bootloader is checking the status (locked) .. then checking the FW (stock) ... DRM-Keys still valid.
But due to the root access you were also able to modify system files and apps can recognize that you have root access. So you can still use the bravia engine for example (DRM-Keys are ok). But the Google Play Store will still recognize that you have root and will not let you download movies.
This is my experience with Root ... If something is not correct, please correct me
UserX10 said:
Hi,
maybe I can help you.
Bootloader is like the BIOS of a PC. It checks everything at start up.
Locked Bootloader only allows to run the Stock FW and in this case the DRM-Keys are working (everything is checked and safe)
Unlock the Bootloader means you were able to install an modified / other FW and then you loose the DRM-Keys (the manufacturer hasn´t checked the FW and it is in the eyes of an manufacturer "not safe". You will also loose your warranty.
If you unlock the bootloader Root is always possible as I know.
In this case the system is not from the manufacturer and unofficial modification could be done to the system. Normally all modified Systems have Root access. So you were able to do things that the manufacturer has normally not allowed. Modify system files or something like that. Also it could be possible to copy for example a downloaded and payed movie to another device. This is why you were not able to download a movie on the Play Store if you have root. On a locked bootloader the FW (system) does not give you the possibility to copy the movie to an other device and everything is "safe" (from the view of companies). No illegal copies are possible. (DRM-Keys)
Since some days Root is also possible on a locked bootloader.
The bootloader is checking the status (locked) .. then checking the FW (stock) ... DRM-Keys still valid.
But due to the root access you were also able to modify system files and apps can recognize that you have root access. So you can still use the bravia engine for example (DRM-Keys are ok). But the Google Play Store will still recognize that you have root and will not let you download movies.
This is my experience with Root ... If something is not correct, please correct me
Click to expand...
Click to collapse
Hi and thanks a lot for your reply, helped me understand the difference of both better!
If I only root but do not unlock my bootloader will I be able to do anything other than using custom firmware (ROMs)? Will I be able to install Apps that require root or install custom modification like the ones offered on this forum that need to be "flashed in recovery" if I only root not unlock my bootloader?
Also, still looking for some pros and cons (my second question in the original post).
Appreciate all your help!
root will give you access to recovery (in time - still in development) and you can install apps that require root access
custom mods - yes you can install them via recovery and some can be installed with root access and without recovery
if u unlock bootloader you will lose bravia engine not sure bout gracenote as i dont use it
you can check this thread http://forum.xda-developers.com/showthread.php?t=2154310 too see what have people wrote bout
rooting with unlocked bootloader
The main thing pointing me towards unlocking bootloader (I'm already rooted on locked bootloader) is being able to install kernels and major roms.
For example, you could flash Doomlords kernel and over clock the processor a bit, but you could also reduce power and save battery
The major roms I speak of are the ones that are kinda cross device: CyanogenMod and Paranoid Android to name 2. CM is based on pure android, no Sony changes so we can't flash that on locked bootloaders as it requires changing kernel. PA is same.
As for the downsides. I'm not too bothered about DRM keys. I use Spotify for music so don't think I need gracenote. Never watched a movie on my phone. BE2 isn't my cup of tea... Over saturates everything.
I'm going to look into DRM keys more tomorrow, but if someone can correct anything I've written then please do
Not being able to restore via Sony tools... Isn't that bad as you're going to be using flash tool a lot so you'll be used to that. Just keep a generic stick firmware .ftf around in case something goes horrendously wrong (usually recovery backup is enough I think).
Sent from my C6603 using Tapatalk 2
Nice thread, I had this question too
It's my first android and I guess I should unlock the bootloader and then root, this way I won't have to wipe my data later when I decide to try cyanogenmod or something else?
Also what happens if sony release 4.2? Will I lose my bootloader unlock and root?
Al Gore said:
Nice thread, I had this question too
It's my first android and I guess I should unlock the bootloader and then root, this way I won't have to wipe my data later when I decide to try cyanogenmod or something else?
Also what happens if sony release 4.2? Will I lose my bootloader unlock and root?
Click to expand...
Click to collapse
I would say root without unlock for now.
When you want to try cyanogenmod or others. Just backup everything using titanium backup and then u can restore after unlocking.
Rooting with a locked bootloader means sony are not aware your bootloader is unlocked
Sent from my C6603 using xda premium
Thanks for all your replies, helped me out a ton!
I think Im gonna root without unlocking bootloader for now to get my feet wet and get a grasp of it's capabilities and limits. Can always restore the phone if I screw up and can always unlock bootloader later if I need it.
Al Gore said:
Nice thread, I had this question too
It's my first android and I guess I should unlock the bootloader and then root, this way I won't have to wipe my data later when I decide to try cyanogenmod or something else?
Also what happens if sony release 4.2? Will I lose my bootloader unlock and root?
Click to expand...
Click to collapse
If you unlock Bootloader, you shouldn't update from Sony. Since you've (hypothetically) already unlocked, you already have 4.2 avaliable from FXP and if you really want the Sony Update maybe you could flash it via flash tool. Bootloader unlock will never be lost (until someone can create an explicit relock file, but customs roms won't relock it). Root maybe lost if you flash a rom without it but you should be able to get it back easy.
With locked bootloader, we have to wait for Sony to bring 4.2 as we can't access the kernel, but we retain the ability to use the official updates. If we're rooted and we update, we are no longer rooted and we may be unable to use the same exploit.
Sent from my C6603 using Tapatalk 2
Related
Hey guys/gals
i have a quick question.
what exactly is the difference (featurewise) when it comes to rooting with an unlocked bootloader and rooting with a locked one?
i'm pretty new to android (iOS user until last saturday), did some research today, but didn't really find much usefull information.
main reason i want to root (at least for now. i'm sure i would find more after spending more time with my xperia), is because i want to format my 64gb SD to exfat and move apps over to it.
thanks guys
edit: and no, i'm currently not thinking about getting a different theme/loader on it (this is one of the things you can only do with an unlocked one, right?)
edit2: and yes, my bootloader can be unlocked
dottore. said:
Hey guys/gals
i have a quick question.
what exactly is the difference (featurewise) when it comes to rooting with an unlocked bootloader and rooting with a locked one?
i'm pretty new to android (iOS user until last saturday), did some research today, but didn't really find much usefull information.
main reason i want to root (at least for now. i'm sure i would find more after spending more time with my xperia), is because i want to format my 64gb SD to exfat and move apps over to it.
thanks guys
Click to expand...
Click to collapse
Ok unlocked bootloaders = you lose DRM keys forever and Bravia Engine doesn't work. Relocking won't get them back. You can also overclock/underclock CPU with unlocked bootloader. You can also flash custom ROMs/kernels with unlocked bootloader.
Now with locked bootloader you can still have root but you don't lose your DRM keys. You can't flash custom ROMs/kernels or do any overclocking/underclocking.
That's all I can think of.
yeah, i read about that whole DRM thing. i don't care so much about the Bravia Engine and DRM, but i wouldn't mind it staying (first time i said that about DRM), so thats one of the main reason i didn't just went on with unlocking.
is flashing a custom kernel something more or less common when using a rooted android? could i get the things mentioned done without doing it? (i think i read moving apps only needs root, but then again: the xperia z seems to be a bit special when it comes to extSD)
thanks for the fast reply
shadowboy23 said:
Ok unlocked bootloaders = you lose DRM keys forever and Bravia Engine doesn't work. Relocking won't get them back. You can also overclock/underclock CPU with unlocked bootloader. You can also flash custom ROMs/kernels with unlocked bootloader.
Now with locked bootloader you can still have root but you don't lose your DRM keys. You can't flash custom ROMs/kernels or do any overclocking/underclocking.
That's all I can think of.
Click to expand...
Click to collapse
is flashing a custom kernel something more or less common when using a rooted android? could i get the things mentioned done without doing it?
Click to expand...
Click to collapse
Well it's up to you. You can either flash custom ROMs/kernels if you want but you will need to unlock the bootloader to do that. Locked bootloader you can only have root and that's it sad to say. But you don't have to flash a custom ROM or kernel if you have root. because you can't anyway with a locked bootloader. Having root just means you can use apps that need root access.
shadowboy23 said:
Well it's up to you. You can either flash custom ROMs/kernels if you want but you will need to unlock the bootloader to do that. Locked bootloader you can only have root and that's it sad to say.
Click to expand...
Click to collapse
ok, thanks. i think i'll stay with the locked one for now...let's see for how long
Hi all,
I have a stock Xperia Z at the moment. Its a work phone.
I want to root it but because its a work phone I have to know I can go back to complete original state if I want to.
Now I have read the threads about backin up your TA partition but I am not sure if by doing this and also by having a stock image I can go back to 100% original?
I read this thread: http://forum.xda-developers.com/showthread.php?t=2234627
Few questions:
- If I root the phone - does it do anything permanent or can I then just loose root easily and go back to exactly how it is now?
- What exactly is the difference between rooting your phone and unlocking your boot loader?
- If I backup the TA partition using the steps in the thread provided above, can I then just do anything else I want to the phone and then restore back to original or are there other steps? and if so, what are they.
Any and all up to date information from someone who knows what they are talking about hugely welcomed.
More nervous than usual just because its a work phone (rooted and used to Custom ROM my HTC Sensation all the time but didn't care as it was my own phone).
Thanks
No one?
Sent from my C6603 using Tapatalk 4 Beta
nnila said:
Hi all,
I have a stock Xperia Z at the moment. Its a work phone.
I want to root it but because its a work phone I have to know I can go back to complete original state if I want to.
Now I have read the threads about backin up your TA partition but I am not sure if by doing this and also by having a stock image I can go back to 100% original?
I read this thread: http://forum.xda-developers.com/showthread.php?t=2234627
Few questions:
- If I root the phone - does it do anything permanent or can I then just loose root easily and go back to exactly how it is now?
- What exactly is the difference between rooting your phone and unlocking your boot loader?
- If I backup the TA partition using the steps in the thread provided above, can I then just do anything else I want to the phone and then restore back to original or are there other steps? and if so, what are they.
Any and all up to date information from someone who knows what they are talking about hugely welcomed.
More nervous than usual just because its a work phone (rooted and used to Custom ROM my HTC Sensation all the time but didn't care as it was my own phone).
Thanks
Click to expand...
Click to collapse
1 - Rooting only changes things on the software side. So it allows you to get complete access to the system files and execute low level actions. So it doesn't do anything on the hardware side. That said, is your phone customized by your employer? Does it have anything specifically done to it? In that case two things might happen. The software is so customized that if you root it and flash a custom ROM on top of that, you WILL lose all the original apps and settings. So there might not be anyway of getting back to the original state. Secondly, your employer might have locked the bootloader permanently. This, I shall take up for answering your next question.
2 - As I mentioned, rooting is only a software level hack that gives unrestricted access. However, let's say you need to flash a custom KERNEL or flash CyanogenMod/AOKP/AOSP (based ROMS), then it's absolutely necessary to unlock your bootloader. This basically is telling the bootloader (which loads your kernel) to allow any unsigned kernels .i.e. non-stock kernels, to be flashed on to your phone. Now mind you, this will cause the DRM keys in your phone to be erased which means you will lose Bravia Engine enhancements for your Pictures. It does remain for the videos though. Lastly, you can relock your bootloader. But you can never get back the DRM keys and hence the Bravia Engine.
So you can either root by unlocking your bootloader or by using root exploits while keeping your bootloader locked.
3 - Since your bootloader is locked right now, I suggest you use DooMlord's rooting toolkit
Here's the link:
http://forum.xda-developers.com/showthread.php?t=2327472
Click to expand...
Click to collapse
Also, backing up the TA partition is only necessary if you want to unlock your bootloader. This aims at backing up your DRM keys so that you can flash them back when you want to relock your bootloader. However this method is still dicey and I wouldn't recommend it considering it is a very risky method and can easily hard brick your device.
Upshot: Locked bootloader - Use Rooting toolkit. Will retain DRM keys.
Unlocked bootloader - For custom Kernels and CM Roms. Will lose DRM keys.
nnila said:
Hi all,
I have a stock Xperia Z at the moment. Its a work phone.
I want to root it but because its a work phone I have to know I can go back to complete original state if I want to.
Now I have read the threads about backin up your TA partition but I am not sure if by doing this and also by having a stock image I can go back to 100% original?
I read this thread: http://forum.xda-developers.com/showthread.php?t=2234627
Few questions:
- If I root the phone - does it do anything permanent or can I then just loose root easily and go back to exactly how it is now?
- What exactly is the difference between rooting your phone and unlocking your boot loader?
- If I backup the TA partition using the steps in the thread provided above, can I then just do anything else I want to the phone and then restore back to original or are there other steps? and if so, what are they.
Any and all up to date information from someone who knows what they are talking about hugely welcomed.
More nervous than usual just because its a work phone (rooted and used to Custom ROM my HTC Sensation all the time but didn't care as it was my own phone).
Thanks
Click to expand...
Click to collapse
-Root ---U can get back your device unRoot by update your device via SUS.
- ROOTING and Unlock BL very difference.
Root >> i can only reach your device till system app or modified many thing in system exclude kernel. and i cant install MOD ROM that need kernel from that ROM.
Unlock BL -- U will loss DRM key your device but u can install may MOD rom or new kernell with good features. and u always can root your device with easy
About TA idk to much and only do backup here, not want to restore it coz can get Hard Bricked my device.
only that i know.... and im sorry for my poor English.
maybe other ppl can explain more or u can search by yourself in android development section.
Sent from my C6602 using xda premium
nnila said:
Hi all,
I have a stock Xperia Z at the moment. Its a work phone.
I want to root it but because its a work phone I have to know I can go back to complete original state if I want to.
Now I have read the threads about backin up your TA partition but I am not sure if by doing this and also by having a stock image I can go back to 100% original?
I read this thread: http://forum.xda-developers.com/showthread.php?t=2234627
Few questions:
- If I root the phone - does it do anything permanent or can I then just loose root easily and go back to exactly how it is now?
- What exactly is the difference between rooting your phone and unlocking your boot loader?
- If I backup the TA partition using the steps in the thread provided above, can I then just do anything else I want to the phone and then restore back to original or are there other steps? and if so, what are they.
Any and all up to date information from someone who knows what they are talking about hugely welcomed.
More nervous than usual just because its a work phone (rooted and used to Custom ROM my HTC Sensation all the time but didn't care as it was my own phone).
Thanks
Click to expand...
Click to collapse
If you backup your TA partition, you can restore it later. This doesn't include anything other than the TA partition.
Rooting the phone just means that you have root access just like on any other linux distribution. You can fully unroot at anytime without any problems. Flashing an unrooted ROM or flashing the original ftf will remove root.
Rooting implies getting root access. You have higher privileges & apps that run as root have higher privileges. Unlocking the bootloader gives you access to protected partitions. The only real question is, do you want to use a custom kernel? - If you do, then unlock. Some ROMs, such as CM, run on custom kernels, so if you plan on using such ROMs, you need to unlock.
No, backing up TA is not enough, Follow this thread to get yourself a full ftf for your current customization that can be flashed with the official flashtool for Unlocked bootloaders or the unofficial flashtool that works with locked bootloaders. Further, you also need to relock your bootloader to fully return back to the original state.
If you aren't comfortable with doing all this, don't.
The next time you want to ask a quick question, please post in the Help Thread.
These questions are nothing new, already been answered multiple times, just adding to the clutter in the Q&A forum.
ZR is my very first Android phone, so basically I know nothing about Android.
I unlocked the bootloader couple of weeks ago following the official Sony instructions in order to flash the stock Taiwan ROM (cause China's ROM doesn't support Google service). But now I found that I cannot update via Sony. More importantly, it's actually not necessary to unlock the bootloader for flashing ROM and/or get root privilege. So I'm desperately seeking the way to relock the bootloader.
I found some guy talking about flashing a small file called Xperia_Relock_bootloader.ftf. But he said that it was only for old models. Anybody here can help? Thanks in advance!
P.S. They said that after unlocking the boot loader, Bravia Engine and TrackID service will gone. But I have both working still. Weird. Does that mean I can backup my TA partition still?
Until a few days ago, I didn't want to do anything involving rooting with my Xperia Z just in case I messed anything up but since Towelroot came out, I went ahead and used it to root my phone without any problems but now I have some questions.
Now that I have root access on my phone, if Sony releases an OTA firmware update, does this close the root access?
My next goal with my phone is to try and cut out as much bloat as possible from my Xperia Z but I'm worried I might get rid of too much things that I might render it bricked. Is there some things I should leave well alone?
Also thinking about trying custom roms but I'm overwhelmed by all the guides so are the guides even from years ago still valid in 2014?
syrupdash said:
Until a few days ago, I didn't want to do anything involving rooting with my Xperia Z just in case I messed anything up but since Towelroot came out, I went ahead and used it to root my phone without any problems but now I have some questions.
Now that I have root access on my phone, if Sony releases an OTA firmware update, does this close the root access?
My next goal with my phone is to try and cut out as much bloat as possible from my Xperia Z but I'm worried I might get rid of too much things that I might render it bricked. Is there some things I should leave well alone?
Also thinking about trying custom roms but I'm overwhelmed by all the guides so are the guides even from years ago still valid in 2014?
Click to expand...
Click to collapse
Updating firmware will remove root
If you remove system apps you wont get OTA
Custom roms require unlocked bootloader which will void your warranty and you wont get OTA
Look up in the forums for latest guides
OTA shouldn't remove root. Root gets removed if you flash with flashtool, sus or pcc
Sent from my C6603 using XDA Premium 4 mobile app
syrupdash said:
My next goal with my phone is to try and cut out as much bloat as possible from my Xperia Z but I'm worried I might get rid of too much things that I might render it bricked. Is there some things I should leave well alone?
Click to expand...
Click to collapse
If you remove something wrong, just flash a ROM again. But like always said: Don't remove something, if you don't know what it is.
syrupdash said:
Also thinking about trying custom roms but I'm overwhelmed by all the guides so are the guides even from years ago still valid in 2014?
Click to expand...
Click to collapse
How to unlock bootloader for custom ROMs: http://forum.xda-developers.com/xperia-z/development/tutorial-xperia-z-zl-bootloader-t2153261
Don't forget to make a TA-Backup!: http://forum.xda-developers.com/showthread.php?t=2292598
Quote by devshaft from the TA-Backup thread:
Backup TA can backup and restore the TA partition of the device. When you create a backup before unlocking for the first time, then you will be able to restore to full factory state (including a locked bootloader). This means all DRM keys intact, Bravia Engine working in Album and last but not least your warranty when needed
Click to expand...
Click to collapse
Like androidtweaker1 said, unlocking the bootloader will void your warranty. The TA-Backup includes some unique data from your device(!), which will be removed for ever if you unlock your bootloader. That's why you should make a TA-Backupfirst, to keep this data.
There are 2 ways how SONY take a look at it if you unlocked the bootloader:
- They take a look in the servicemenue
- Or they take a look at if the DRM-keys(which are included in the TA-Backup) are in your device
If you relock the bootloader only, they will see in the servicemenue that it is locked. But if they take a look at the DRM keys and they aren't available, it's clear for them that you unlocked your bootloader.
If you want to send your device to a repair center, just relock the bootloader and restore the TA-Backup. There are also some threads about it, so don't be afraid to search for it. And one more thing: Never, and really never restore the TA-Backup from an other device, it will hardbrick your phone!
So the root process is a matter of unlocking the bootloader and flashing a new boot.img that includes CWM.
You're supposed to backup your TA partition to preserve your DRM keys.
There's some talk about a bunch of things that can be lost with the DRM keys -- camera quality, Triluminos, Bravia, etc.
Are these lost when the bootloader is unlocked, or only if TA is not restored?
If I backup TA, then unlock the bootloader, then dd TA image back into the partition (after rooting, I presume?), will that restore the camera quality, Triluminos, etc.? Is it possible to root without losing those things, or is it a choice? Because I don't think I want to root quite that badly...
This is my first sony phone so I don't know too much about backing up and flashing things on this particular phone yet, but it is my understanding that there is no way to root without unlocking the bootloader at this time. Unlocking the bootloader wipes the TA partition so that's where the loss of the DRM keys comes in. Unfortunately, in order to back up the TA partition, you need root. So, right now, it's a catch 22 until someone can figure out how to root the device without unlocking the bootloader. I'm personally going to wait it out. There's too much about this phone that I like about the stock sony experience with this device to lose a lot of functionality and have degraded camera quality. The only reason I would root is to be able to backup certain things and run xposed. Not worth unlocking the bootloader just to have those things IMO.
In order to get root access, right now you have to unlock the bootloader. In doing so, you erase the TA partition. So, once you have root access, you don't have a TA partition to backup anymore.
If you care about your TA partition, then wait for an exploit to be found that enables root access without the need of unlocking the bootloader. When (not if, problem is just when) this happens, you can have root access, unlocked bootloader and TA partition altogether. (that is, unless you've already unlocked the bootloader... in that case, you don't have a way to restore your TA)
Ah. So we cannot even read the partition without root?
So yes, then I will just have to wait until someone finds an exploit.
This rises another question for me.
Assumed there is a way to root the phone without unlocking the bootloader. If one does
* backup the TA partition
* unlock the bootloader
* install a custom recovery
* restore the TA partition (bootloader locked again)
Is the phone still rooted? And, even more important, is the custom recovery still there?
I guess this can be answered by someone having experience with earlier Xperia devices like the Z, Z1 or Z2. I've already been searching for the answer, but couldn't find it so far.
Cypher_01 said:
This rises another question for me.
Assumed there is a way to root the phone without unlocking the bootloader. If one does
* backup the TA partition
* unlock the bootloader
* install a custom recovery
* restore the TA partition (bootloader locked again)
Is the phone still rooted? And, even more important, is the custom recovery still there?
I guess this can be answered by someone having experience with earlier Xperia devices like the Z, Z1 or Z2. I've already been searching for the answer, but couldn't find it so far.
Click to expand...
Click to collapse
You might be better served visiting other sections of XDA, such as the Z1 Compact and Z2 forums here on XDa. They will be able to give you a little better glimpse into the future for how things are done.
Cypher_01 said:
This rises another question for me.
Assumed there is a way to root the phone without unlocking the bootloader. If one does
* backup the TA partition
* unlock the bootloader
* install a custom recovery
* restore the TA partition (bootloader locked again)
Is the phone still rooted? And, even more important, is the custom recovery still there?
I guess this can be answered by someone having experience with earlier Xperia devices like the Z, Z1 or Z2. I've already been searching for the answer, but couldn't find it so far.
Click to expand...
Click to collapse
Relocking the bootloader when a modified stock firmware and a stock kernel with recovery is installed results in a device that doesn't boot, so I guess no, although I don't know which part exactly breaks in the process.
My understanding is that with a custom/unlocked recovery, you'll lose the TA partition with DRM keys. So you'll lose out on anything that needs the DRM keys. If a root exploit is found, then you could use the standard ROM with root and not touch the bootloader/recovery/TA partition. But as soon as an update rolls out, you'll lose root again (and likely the exploit with it).
Backing up the TA partition means that you can restore it to stock (i.e. to sell or for warranty repair).
Again, as per my understanding - any AOSP/CM based ROM will lose any of the Sony proprietary software and features anyway, no different to Samsung or HTC in that respect. I remember having a HTC One (M7) last year where the camera was worse on CM because HTC used their own post processing software within their camera app.
In theory, it may be possible for someone to come up with a stock based ROM with root baked in that keeps some the Sony proprietary software etc, but this is unlikely I would say.
I'm thinking about buying a Z3c, but it sounds as though there with be no AOSP rom with all the display and camera enhancements. The most concerning thing is that there is no way to go back completely to stock as you can with a Nexus for example. Maybe I should just hope for a Z3c Google Play Edition? I'm going to have to check the other Z phone forums to see how big of a factor this is.