I would not recommend buying a Z1c at the moment, not until it is seen if Sony bother to fix issues in the phone software. Unless you are happy to unlock + root, then go ahead.
The stock Sony software has so many quirks at the moment its driving me nuts!
- calls answer to speaker phone sometimes
- sound enhancements/ equalizer only works for walkman app
- fast dormancy is broken, causes high battery drain
- "superior auto" on the camera is a disaster in low light/ flash photo
- Some intermittent weirdness with notifications and LED caused by stamina mode
- volume randomly reducing itself and volume warning sporadically appearing
- Some compatibility issues with 3rd party browsers
- proximity sensor issue: 1-2 second delay in screen switching back on if it was switched off by proximity sensor. i.e when you make/receive a call, you have to wait to hang-up the call. minor inconvenience really.
And as already mentioned, the plastic ASF on front and back glass is very, very delicate. Leave the phone wrapped in cotton wool until you have protectors on front and back!
oh, and buy a dock or magnetic charging cable too, otherwise the USB flap comes loose (mine has after 3 weeks)