I think it would be pretty tough to have both enough experience with lots of sound cards, and a good way to objectively really get an accurate test as an end user as to their performance/quality.
Case in point, I never had a sound card issue of any kind untill I started using TV capture cards, then I ran into a couple, noise being introduced into the sound card became a problem, also started having problems with power line noise occasionally creeping into the mix.Neither of these is really sound card related, but it does show how other things can influence sound quality.I honestly cant tell the difference in sound quality between a 10 yr old soundblaster 16 and one of todays new sound cards all else being equal.Its never as good as high quality analog and never will be.Best thing I ever did was connect my systems to a good stereo amp and speakers and experiment with card placement in the PC to minimize any noise that can creep in,other than that, I really doubt a high dollar sound card will sound that much better than a decent low dollar model, im sure many will disagree with that, but go check out someone else's setup and see for yourself, too easy for the placebo effect to affect one's judgement after spending big $$ on a new card.