I'm studying abroad in the Fall, and figured I need some sort of portable backup solution to bring with me. I'm decided on the best way to do it, though. What I'm considering: 1. (simplest) Buy a 320Gb Passport and use it as an external. 2. (fastest) Buy a 200Gb 7200rpm drive and replace the on in my MBP, then get an enclosure for the 160Gb drive that I take out. 3. (largest) Same as 2, but a 320Gb 5400rpm drive instead of a smaller, faster one. I'm tempted to go with 1 because I don't want to screw up the installation of the hard drive on my one and only computer. What do you guys think? What kind of difference in speeds would I see in a 7200rpm drive vs the 5400 drive I've got?