Sonos SUB Review - SlashGear:

"When you decide to pick up a Sonos speaker, you decide to jump into an ever-expanding ecosystem of both hardware and software, with a brand that’s dead set on pushing an immersive experience out to the customer. With the newest member of the family, the Sonos SUB, you’ve now got an earth-rumbling bass component in addition to a couple of sets of high-quality speakers and several center points – dock, bridge (hub), amplifier, whatever you want. The big question you should be asking yourself here is not just if you want to work with the magic that is the SonosNet wireless mesh network, but if you feel its necessary to pick up more than one of the Sonos family components."