Try the OWC "on-the-go" drives. (That's Other World Computing; sorry.) I don't have one, but I keep looking at them for the portability. I know you can get them in various 400/800/USB2 configurations, and I'm nearly positive they have them at both 5400 and 7200 rpm. I have two other OWC drives (full size) and have not had any issues. And when I did have a question on the settings for an internal drive, on a Saturday no less, their customer service was great.