I have had the same question as I am beginning to experiment with computer audio. My current system consists of a Toshiba Satellite laptop (Vista), XMPlay, Wasapi, Farstone Virtual Hard Drive Pro (RAM storage playback), and Edirol UA-5 USB interface. I also auditioned a much more expensive Audio Note Dac 1.x Sig. I found the UA-5 to have a larger soundstage, more detail, and dynamics. Also, the superior "warmth" and musicality associated with all tubed dacs is, at least to my ears, a myth.