I like them a lot.
I the best setup I had been using was an M-Audio DMP-3 into an M-audio delta44 card. The firepod is a noticeable step up from that setup. I don't know whether the pre's in the firepod are better, or the A/D conversion is better, but it was a step up.
If you want to hear it in action, go
here. Everything that plays in that player was recorded through my FirePod. Electric guitars and bass were direct, acoustic and vocals were mic'd. Drums are loops.
I'll just add also that I love my firepod. The simple layout and the controls on the face of the box are perfect, for what I do, anyway. The "mix" knob (mixes your inputs with the playback levels) is invaluable to me now. I don't know how I'd go on without it.