I've got the Sonos 5.1 system, two 1's, soundbar and a sub. The sub alone is fucking ace.
One thing to watch for with the soundbar is that there is no hdmi input, optical only so if you're like me Xbox/sky etc it all has to go through a switcher as there's only one optical in. My switcher was only £20 but it was the dicking around that pissed me off.
For music we use apple, £15 a month for the lot of us. Works really well through the Sonos app but for some reason you do get the odd song that won't play (copyright I presume)?