if you are going for more storage, then get the raid 1 setup linked from b&h by tim, that's 2 drives, 1 tb each, that are mirrored, so each drive has a complete photo, one drive goes bad, no data loss, replace the bad drive, run the back up software, and back in busines with redundant copies and pick up a couple of large cf cards, maybe 8gb each, they are getting pretty cheap now, and as tim says, those are huge files