Have now had my ZP90 (Connect) for three years and it runs like a clock. Had a while problems with playback sometimes stopped in the middle of songs (do not know if it's because Sonos: one or the network) but this problem I now have not had in over a year.
I plugged it into my stereo amplifier and streams music in WAV and FLAC format to the amplifier / speakers via my NAS.
The sound is good, although not top notch compared to eg CD players. It certainly plays music in CD quality (16 bit) but no high resolution 24-bit music, do they want it to get buy a Pioneer N-50 or any other streamer.
I do not use multiroom feature, which of course is perhaps Sonos main strength, and that day it pops up a product with equally good user interface that Sonos and capable of high resolution music I change enough out, even though it is otherwise a top-class product.
The user interface is really good on both the computer and the iPod. Additionally, the Sonos including Spotify and Wimp. Waiting, however, that there will come a originalapp from Sonos for WP8 so that I can control it via my windows mobile (there certainly Sonos apps from independent producers for WP8) so I do not have Apple's isolated and expensive environment.
Aside from Sonos: one does not support high resolution music, I'm really happy and can not recommend this product.