Hello all. I think I am going to guy an iPod mini and I don't really need the 6Gig model but a review I read said it had better battery life and slightly better sound quailty than the old 4Gig. I was wondering if apple implimented these imporvements into their current 4Gig models now as well or if it is worth the $50 to get the 6GB model. Thanks all.