I have them also, they sound pretty good without a headphone amp. I'm using Xonar DX with Dolby Headphone. The slightly lacking stock bass is compensated for by both Dolby Headphone and the equalizer. I would recommend these headphones as long as you pair them with a soundcard, Xonar DG at minimum (has both DH and amp). Very comfortable too.
If you don't need the mic (which is great quality btw), look for pure headphones instead of a headset.