I have a follow-up question too, for ibookuser or whomever would like to comment:
How well do either of these drives work with Windows PCs? Obviously, they'd have to be Win formatted, but do they require installation of any software, or are they truly plug and play? And would it be possible to partition one into a Win partition and a Mac partition and have the Win computer be able to use that partition? I'd be wary, I suppose, of formatting the whole darned thing in a Win format.