I did a little bit of searching but didn't find the answer I was looking for. I'm trying to decide between these two drives: http://www.amazon.com/LaCie-Desktop...2?ie=UTF8&s=electronics&qid=1251042742&sr=1-2 and http://www.amazon.com/LaCie-FireWire-External-Poulton-301315U/dp/B00170M64K/ref=pd_cp_e_2 I'm wondering if the speed difference with Firewire 400 over USB 2.0 is worth the extra $30. I'll primarily be using this for Time Machine backup, but also to store other large files when necessary. Any recommendations? Thanks.