Howdy
I have the 320 or 350 gig version of that drive. It is rather nifty as the FireWire module is swappable with the USB/ESATA (yes both on the same module) module (it just screws out from the bottom of the drive).
I'd say if you don't have ESATA, maybe spend a bit more and get the firewire version (especially if you intend to copy over large sized files) While USB2 might offer higher data speeds the firewire can sustain it's speeds much better and thus is actually faster when copying over larger files.
And a firewire card for a pc is under R200 I think (i had to get myself one - but soo happy I am)
ps. from what I've noticed, using firewire doesn't suck the life/speed out of a pc like USB does!! - just an observation.