Agentless Backup is Not a Myth
All four devices have Ethernet ports, though the Sonos system comes with two which could come in handy if you want to add a PlayStation 3 or the like to your network. The Roku, Logitech and Sonos come with digital optical and coax, and analogue connectors. The Philips lacks an optical connector but adds a 3.5mm headphones socket. The Roku's analogue audio output actually is a 3.5mm audio port rather than the usual RCA so it doubles up as a headphones jack.

Round the back: the Roku
One major difference between the Sonos system and the others is that it relies on a bespoke wireless mesh technology rather than on good old 802.11 Wi-Fi to communicate with itself.

Round the back: the Philips
The short and tall of this is that if you live in a mansion the Sonos system's units can be expanded ever outward to cover a huge area. For those of us who live in three-bedroom semis and don't regularly feel the need to have Springsteen in the lounge, Mahler in the loo and Dido in the master bedroom, all at the same time, this is perhaps overkill.

Round the back: the Squeezebox Duet
More to the point, to expand your Sonos network to the far reaches of the ancestral pile you're going to need seriously deep pockets. Each new ZP90 will set you back £250, while Logitech only want 99 of your hard earned pounds for an extra Squeezebox receiver. Fair enough, the Sonos bundle will play music in two rooms out of the box, but to do the same with the Squeezebox will still only cost you exactly half as much.
COMMENTS
I am happy with my NP1100
As indicated in your review, set-up is simple for Roku and Philips. I have choosen the Philips because it was cheapest and didn't want to spend too much to test a new technology.
Result is I am very happy with my NP1100 which is quite nice and so easy to use. I am also amazed by the number of station available.
When I have plug-it in the first time, SW has been automatically updated and now BBC is working very well.
I really love this device which allow me to listen internet radio without PC and also all my MP3 on my Hi-Fi system.
Tks for your usefull comparizon.
Problems with Squeezecenter & Ubuntu
If your music sits on a Linux server, check that the Squeezecenter server software works on your machine before parting with your hard-earned cash on the Logitech offering.
There are known problems trying to get Squeezecenter 7.2 running on Ubuntu 8.04 and derivatives. The advice from Slimdevice's support team is limited to telling you to go and read the forums - thanks guys.
I for one have given up with this and am going to investigate the Sonos product.
Aren't these technically a violation of copyright?
After all it is making available to others. If they have a receiver and live close enough they could pick up your transmissions and GOD FORBID copy it onto a cassette tape, then encode it to FLAC (sarcasm).
Honestly though, surely there is a legal question about these devices. They duplicate the copyrighted works don't they. And transmit them to all and sundry.
Bloody Freetards, paying lots of money to make available copyrighted works. I think that you all should pay the artists, no the music labels on a per listen basis.
(....paytard)

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