[Xperia Z1 Compact General] chch:
I came from an Xperia Acro S so the whole experience is easily compared:

My only issues are:

1) Standard 4.4.2 Kitkat update completely eliminated any trace of my GPS. I have no GPS.

2) Language settings (against my specific language) are blank and keyboard input options all use predicted next words rather than showing variants of the keyboard gesture just typed. Damn annoying (to the point where I may use a 3rd party keyboard but I loved the Sony keyboard).

3) The back glass does not feel firmly attached and moves and clicks if I push it near the bottom. Not sure if my unit is waterproof.

4) The speakerphone is bad (on my unit anyway). I can't do a speaker call without the person at the other end complaining about odd noises and cut outs.

5) The new fancy multi-shot camera option puts lots of similar photos into the album (not well thought out). Sometimes it groups then into one photo icon and sometimes it doesn't.

6) The notification light is easily missed because it's more at the top rather than front and you can't change the colour of frequency etc

7) The phone is fast (very fast) and kitkat is fast but Sony still have slowish transition effects in their own apps.

8) The Z1C can be docked but no docks are available in my country. The Xperia Acro S came with a doc.

9) The autolighting seems very odd (hit and miss) but I like using manual anyway. I had to use an app for quick settings on the Acro S but the Z1C toggle is fine.

10) I had more screen for browsing on the Acro S. The Z1C has navigation buttons that the browser does not hide. In fact the Sony Android browser was better than Chrome (where the hell are all the settings) but the Sony browser is not on the Z1C.

My biggest issue is that I had to buy a limited warranty import because the phone is well priced and none of the telcos in the telco cartel mafia in my country wanted the phone in the country and so Sony does not sell the phone here or any of the network providers.

I don't have the WiFi and network issues mentioned earlier. My connection is as good or better than the Acro S. I am impressed at how good the LTE connection holds up even when you are far away from a 4G tower and down to 1 bar. Battery was great before 4.4.2 but I have not been on Kitkat long enough to comment.

It is a friggen nice phone. Most issues are software for me. I very much want my GPS back!

---------- Post added at 08:38 AM ---------- Previous post was at 08:21 AM ----------

I have to agree that the whole power button and volume together takes some getting used to.

Regarding the 'pinky' issue. Same here when I first had the phone. The grill on the bottom is like sandpaper on your pinky if it moves about and the square edges don't help. I think I have subconsciously learned to hold this phone differently as it is no longer an issue. The power button sticking out a little is great because if you put your thumb below it it stops the phone slipping downwards (which is what your pinking was doing leaning against the bottom grill) and it feels more comfortable overall imo.

I am also a one handed phone user (really hating the 2 finger swipe for Quick Toggles in Kitkat as you can't use your thumb).