Can I get some opinions on this? I can get a 20Gb Zen for 430 plus tax or a 15Gb iPod for 547. As far as i can tell the Zen is a little bigger, and has batteries that last about 4 hours longer. but the iPod has more features and an expansion battery pack that takes 4AA batteries which I really like. one feature the Zen has that Im not sure the iPod has is you can use the Zen as a portable harddrive can you do the same with the iPod ie have non music files stored on it so you can transfer them to another comp?