I have this in my setup, it works just fine and gives you options for audio capture if you need it at any time.
It is USB bus powered, which means that you'll need the computer to be on for it to work, but if your music is on the computer, no problem.
It does have an otical input connection, but as the unit is being powered by the computer, the audio is transferred via USB too, so I have never had a need to use it.
There is an externally powered version, the FA-66, but this is also a Firewire interface and being more expensive, puts you into Beresford Caiman territory. The UA-25EX (latest version) can be had mint for under £100.
The outputs are RCA and balanced connection via 1/4" Jack sockets, so standard hifi and monitor type speakers are catered for.
Sound quality wise, it's as good as I have heard, but I am sure better is available (at a price). I have considered an upgrade in the past to give me more input options and the ability to use it without the computer being on, so the DACMagic Plus is on the cards, but I have no sound quality issues.
It will accept up to 24bit/96Khz file types.
Not a lot else to say really, it cost me around £80 delivered, so nothing to grumble about at all.