Share your experience!
Hello Sony,
recently I updated my phone to the newest version,
here is my opinion :
1. PERFORMANCE UPGRADE
- pane to pane animations are now smooth like on Android 4.1 ver .253 = very good!

- stock web browser scrolling (Chrome) is now smooth like a charm!

- "tools" widget is now smooth, before on 4.2.2 it was stuttering, now the problem is fixed 
- Album app = when I am viewing a picture in a full screen mode and switching the pictures it is smooth like a charm + I really like the animation

when viewing a gallery and scrolling (a lot of pictures) it is not that smooth but still better than before (I believe it may be corrected in near future).
- Socialife scrolling is not smooth even if I changed available memory in options for this app to 100MB (need to be fixed). 
- settings menu scrolling is better but not like a charm, but again, a little bit better than before 
- seems that game performance is also better but didn't have much time to test it

2. SCREEN
- I don't know what did you do to the screen or it is my eyes only but the screen looks MUCH MUCH BETTER! Contrast ratio seems increased and everything is so crisp and clear! And the colors seems better now

3. LOCKSCREEN WIDGETS
- still missing Walkman to choose. 
- if I will select the camera it will launch, but again if I will switch to another that superior mode, the app will close itself, it is not fixed. 
4. CAMERA
- camera quality seems to be improved in dark conditions

- camera launches faster

I will update the thread as only I will get some more conclusions.
Overall I would like to say THANK YOU! Sony for this update, If you will continue to bring us such updates I will no longer consider switching to HTC.
Guys, and what is your opinion after this update? Feel free to spread the word.
How can I buy a beer for developers? 
Sony needs to increase the salary of its employees after such updates 
5.RAM
- RAM management is now better as the OS consumes less memory
6. SD card
- reading from SD card seems to be faster.
Now I can really feel like Sony cares about its customers, listen to us and gives something back after we give it our money, I no longer feel abandoned like it was with Xperia X10 or Xperia S and will stick with Sony 
Like new CEO 
Looking forward to new Sony flagships here in Poland
Thank you for the positive feedback, it is always nice to see comments like this 
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to be honest this update kept me away from moving to htc or samsung because the previous 4.2.2 on my xperia z was really horrible ... but the main problem that shoooould be fixed is when you landscape your phone when you are watching a movie it takes time and it is not smooth like the I phone 5 and SG s4 and HTC one ... please take this problem seriously ...
Thanks for the reminder where is our update oh yes haven't got it yet in the UK!
THATS SOUND VERY GOOD:)
BUT THE BIG QUESTION, HOW ABOUT BATTERY LIFE, ITS SINKING NOW WITH THE LAST FIRMWARE BUT I HAVE NOT UPDATE TO THIS YET., PLEASE GET BACK:)
Xperia Z Locked BL, UK unbranded firmware 10.3.1.A.0.244 downloaded from PC Companion today, was previously on 434 firmware when device connected to PC
recently downloaded the firmware 10.3.1.A.0.244 from SUS and it is super fantastic!!! love it!:smileyhappy:
Downloaded 10.3.1.A.0.244 from PC companion.:smileycool:
Camera quality improved in dark condition but still it takes time to launch.
Viewing images in albums is amazing. Also moving from pane to pane in menu is much smoother now.
Cheers! Sony