My new Powerbook is about to arrive (my first Mac!) and I want to get an external hard drive. I can't decide between the 400Mbps Lacie Porsche drive and the 800Mbps Lacie d2 drive. I've never used a laptop as my main computer before, so I'm not entirely sure how I'll be using this external drive, but I guess I'll store my music and video files and such on it, and maybe make a daily backup of my whole laptop... Do you guys think it's worth it to spend $60 extra to get the 800Mbps? Thanks!