First of all: Hi! Long-time reader, etc., I made the switch back in June with the new MBPs, and I'm pretty much smitten with it. Anyway... I've been reading a bunch of threads here and elsewhere about external HDDs, but sometimes I feel even more confused after reading than I did before. Basically, I'm looking to use my MBP (at least part of the time) as a dual-OS HTPC, including DVD and hi-def. My requirements are: FW400, 500GB or higher, compatible with (and readable by) both OSX and Vista/XP, and as reliable as possible. So, does it matter whether I buy a pre-built setup (i.e., MyBook Pro/Premium, LaCie Porsche, Seagate FreeAgent, etc.) or if I get an enclosure and stick a hard drive or two in (such as the OWC Mercury Elite, which I can also get pre-built)? Any suggestions outside of the model lines I mentioned would also be welcome. TIA.