I'm looking into buying an external hard drive, and I've narrowed the decision down to either the Lacie d2 or Porsche Firewire Drives (250GB, 8MB Cache models). The d2 featuers FW800 + USB 2.0, but weighs in at a realatively hefty 3.3lbs while having some sizeable dimesions. The Porsche only has FW400, but is 1.9lbs and significantly smaller. I guess my question is this - besides the interface differences, what are the real differences between the two models? The d2 seems to be marketed as more professional, but is that just hype?