I do think the apple ones are best - although there are a lot around cheaper and probably very good. The apple interface is the best and also if you want to get a docking station or anything then they are all geared up to ipods. I've got a shuffle and a nano. The shuffle is good for cycling (lightweight, harder to break), the nano good because you can choose playlists/artists/songs (something you cant do on a shuffle).
Also Itunes is very good at managing your computer music and creating playlists etc - much better than the software which tends to come with some of the mp3 players - they spend money on the device and skimp on the software