I've been using my Audigy and it's sounded perfect for the last month.
The only thing is, I'm curous - I have no 4 (or more) speaker support, can't get the rear channel working at all. I was thinking this was due to the WHQL drivers lacking more than basic sound support.
As far as suggestions for a soundcard, people seem to be saying the Gametheater XP is kicking ass in WinXP.
SunnyD
PS - Drivers installed, big whoop. Only difference I see is that it added 6.1 and 7.1 speaker maps to the list, though I'm skeptical if they work.