Whats the deal with external USB drives

[setfree]

I was wondering if anybody could give me information on external usb drives. I mean the ones that are like normal drives except they are in an external enclosure and are connected to a usb drive. The reason I ask is the church I attend just replaced our video editing equipment (were talking ancient here we were using commodore amiga's and im still not sure how that worked out.) with a brand spankng new dual xeon 2.2ghz tower with a dvd burner and 5 scsi drives (1 18gb and 4 73gb) and a 40gb 7200rpm, 2 21in monitors and Video Toaster 2. (a very nice video editing package.) The best part is the insurance company paid for most of it because our previous equipment got burnt out by lightning. Anyway this new computer is back in a room in the back of the balcony and its connected to the sound booth which is were we have a dell 1.7ghz P4 that is connected to a projector and some other stuff. We also have a newer computer in our youth building across the lake (the one in my sig) and we are looking for a way to easily transfer files across the 3. We have already decided to network the two computers in the sound booth with a crossover cable but we needed a way to transfer digital video which obviously won't fit on a cdr. I was looking at some of these external drives and wondered would it be better to get one or get the eternal kit and put my own drive in.