A few years ago a company came out with some DJ softwre that I used to use that solved the dynamic range loss of mp3's. Creative is just doing the same thing with their new cards and software. As you know The concept for MP3's were originally streaming audio that is why they have the dynamic range loss. Supposedly it isn't what we here but I doubt that works for everyone. The X_FI cards from Creative are actually superior cards and the specs are very good. I tried to find them again to post on here and couldn't locate them. Newegg etc. doesn't show the true specs. They do have a better signal to noise ratio, frequency response and stereo seperation. The earlier soundblaster cards were just renamed but still have the same specs, the X_FI cards are of the newest with a whole new chipset. A co-worker of mine is sold on these cards and is a audio nut big time. He only likes the big name audio equipment(must be nice to be rich and no kids) like Bang & Olsen etc, so i trust his opinion when he tells me that these cards make a huge difference.
Sound is like art, it's in the eyes and ears of the beholder. If you are happy with what sounds good to you that's all that matters!