I have played around with many systems, but Sonos is the only wireless systeem that is reliable and doesn't suffer from outages like with AirPlay, Bluetooth or systems such as the B&W a7. I have two Play1s and a Play5 and they are fantastic.
Sonos are great as you say. But reliability varies. My parents suffer occasional dropouts with theirs.
Whereas my B&W Zeppelin Air is rock solid outage wise.
Obviously both of our tales are anecdotal and both B&W and Sonos products have issues.