Gave Sony another chance and recently bought a Z (C6603 in white). This, coming up from a Arc S (LT18i) which had horrendous quality control issues (the cracking above the prox. sensor for one).
Overall, pretty pleased. Well, the first Z I bought had issues with the screen (upper corners looked as if they were being pressed on with pressure; the colours there looked off). Got it exchanged immediately (the new one having a later batch date). Trouble free since. The Z is a good phone.
Updated as soon as I got it home to the 4.3 OS (the .101 variant). I also have a SW2, and with WiFi I've not had any issues. Saying that, there are some bugs which I have experienced, which albeit minor but could easily be addressed:
1). When using the front-facing camera, there is a grey line on the right-side of the image. It's around 50 pixels wide, on the very right-side, and runs down the whole of the image. Resembles an issue with Sony (Ericsson)'s W200 camera from back ages ago. The ISO adjustment part of the camera firmware was buggy and caused all sorts of random issues with pictures that were taken in dark environments; Sony Ericsson actually fixed that issue on the W200 with subsequent firmware updates then. No issues with the rear camera on the C6603 though.
2). When getting a call and picking it up, sometimes it automatically goes to loudspeaker mode immediately. Unsure why, but I'm not alone with this. While my phone is an unbranded variant (generic Sony software), I've got friends who've got carrier branded software who also have this issue. Issue doesn't happen all the time, but I sometimes accept a call on a quiet bus and hear the caller on the loud-speaker rather than the ear-piece... Again, this will require a small code change in the kernal. Shouldn't be too hard.
3). Landscape lock-screen. Got the DK26 dock with this phone. When on the dock, at times the phone randomly shows a landscape lock screen (the keypad on the right side, the clock / music player on the left), but in all cases it automatically switches to portrait mode. Any chance of letting the phone show a landscape lock screen when it's in the dock? It's definitely a feature that seems to be present in the current firmware, but it looks as if Sony's purposely forcing a disable-this-feature flag on this for some reason. If anything, had a similar issue with the Arc S when it was docked to the DK10. And this was a common complaint.
4). Waking the phone up. Pressing the power button sometimes doesn't wake it up? Maybe it's me getting used to the side-button (always used the hardware HOME button on the Arc S), but I need to sometimes press it twice to get the Z to wake. There is a thread with a similar thread detailing this, but my issue isn't as severe (second press always wakes it up).
Yeah. The only bugs I'm having at the moment. The Z is a big upgrade for me from the Arc S in terms of performance and general (build-quality) reliability. And the software support so far has been commendable. Well, compared to the Arc S which was abandoned with the buggy 4.0 update but that's a story for another day...
Pretty sure that Sony will be releasing a 4.4 update soon (I'm hearing late April / early May from my Sony sources). Probably better fixing above issues on 4.4 rather than another iteration of 4.3.
Yeah. My two-cents worth.
EDIT - Something to note. I always factory-reset when upgrading. I did so with my C6603, and the above two bugs still exist.
