I currentlyown and love a 1 gig M240 Sandisk and can't complain about the sound. Unless there is some drastically different implementation of the technology, I can't see any problems. But, I'm using WMA and still get 240+ songs on that 1 gig.

P.S... By the end of the year I will have upgraded to their 4 gig M260. Granted, these don't do too much in the video area but that's not why I buy these things.