Sonos shipped me a review system to try for 30 days, and I thought the sound was great. I already had a mutli-room Sonos system so adding the new portable player was just a matter of plugging it into AC power and pressing two buttons on the S5.
If you don't already have a Sonos system, you have to plug your unit into a router to connect to your music library and the internet. If that doesn't work in your home layout, you can buy what Sonos calls a Zone Bridge (US $99) that plugs into your router and lets the S5 make a wireless connection. Once that basic pairing is made, you can add as many other Sonos music systems as you like, all connecting over a wireless mesh network.
The system sounds quite good, given the limits of the small desktop-friendly size (8.5 x 14.4 x 4.8 inches). There are 5 speakers, two tweeters, two 3" mid-range drivers, and one 3.5" woofer all driven by individual amplifiers. The woofer is a ducted port design and the rear port serves double duty as a carrying handle.