I have a Creative zen at the mo but its rubbish as the headphone socket keeps cutting out. I think Im gonna stay clear of Creative, 5 to 6 gig will do me, hard drive or flash - not really fussed, either would do tbh.
I hear good things about irivers, and the iaudio / rio carbons I havent heard of, not that that would put me off it, as long as they are good quality products.