Office Digital Audiophile System

I've been thinking about putting a nice audio system in my den based around the Sennheiser HD-650 headphones. Don't want to take up too much space. I would rip my cd's to disc on my office computer. Then buy something like a Grace m902 Stereo Reference Headphone Amplifier (also has a built-in DAC) so I could it feed toslink or USB directly from the computer and then listen on the HD-650's.

Does anyone know of alternatives to this? How's the sound quality of the m902?
The Grace is well respected on If you search the threads there, you should find lots of info there.
Check out the Apogee Mini-DAC:

You could run your 650's either from the Headphone jack in the front, or you can get a balanced cable and use the XLR outputs in the back. You can get this with or without USB (it's an add-in card) and there is also a Firewire card coming sometime.

PS Audio is also coming out with a Headphone amp in the next few months - No details yet, but you can follow the discussion in their forum:

registration required for forum:

Sounds like it will have:
USB input only
RCA output (passthrough)
about $799