Here's my take on the whole thing...
I've had the Soundblaster Live Value, the 5.1 and now the Audigy and you know what? I have been unable to really see any difference in any of them.
Sure, lab tests and some advanced features may be avaiable, but from the standpint of just using the thing to listen to music, play games with advanced sound effects etc. - I can't tell the difference.
And I'm used to being able to do so as I am a musician, a not too serious audiophile and an avid gamer.
The higher priced units are nice and do have extra features and connections, however, if you're just looking for playback and sound - get the least expensive and put the money saved into something else.