I have a Seagate 500gb. I use external drives for backup. The Seagate and my current laptop have USB 3.0 ports which are much faster. Flawless. I'd suggest looking to the fastest port on your 'puter and match a drive interface to it. If you have a desktop, you can add a USB 3 card. I hear there's a much faster standard coming soon (isn't there always?).
If that's the invisible man at the door, tell him I can't see him!