I'm trying to figure out if there is a speed advantage for internal hard drives versus external USB hard drives. Current SATA drives claim to be able to transfer data at 3 Gb per second, but the mechanical nature of the hard drive will prevent it from even coming close to that rate. So it seems to me like a USB hard drive will probably not be any slower, especially if it's running at the standard speed of 7200 RPM. Is this correct?