Got a MPB 13". I need a good external drive, but I'm wondering which is the data bottleneck: FW800 or 5400RPM? The reason I ask is I have an old iMac with FW400 and an external Hitachi 7200RPM 200GB 16MB cache in an OWC case that's (suppesedly) capable of FW800. It seems to have taken the same amount of speed to restore a very large file to my iMac (FW400) vs. my new MBP (FW800). I would like to replace this drive with something bigger, but if FW800 is the bottleneck, then I'm thinking I should just get a 5400RPM drive to both save money and get a larger drive. Any thoughts?