I'm looking to buy a used laptop, and was wondering what would probably get me better performance and/or be more reliable. A 900 mhz G3 14" ibook, or a 500 mhz G4 15" tibook? I have found a 15" Powerbook G4 500 w/ 256 RAM, a 20 GB HD, and a DVD drive for $599. While I have found a 14" ibook 900 G3 w/ 128 RAM, 40GB HD and a combo drive for $699. Any advice/opinions anyone can give would be greatly appreciated!