I've almost filled my iMac's hard drive, and so I'm looking at getting an external drive to house my iTunes library. I'm thinking of getting a 3TB drive. The only Thunderbolt drive I can find is a LaCie one that's over twice the price of a comparable USB (2.0 - my Mac doesn't have 3.0) drive. Is it worth, for iTunes in particular, getting a Thunderbolt drive given the extra cost? I have an Apple TV as well, if that makes any difference (would streaming be slowed down?). Or would I be ok to get a USB drive (and perhaps another one for backing up!)? Thanks in advance!