I'm looking into getting myself a server setup of some description. Such as a Mac Pro or xserve with external storage. I've got a number of 1tb drives at the moment and a 4bay external drive that hooks up using esata. I was thinking of getting another 2 2tb drives and putting 2x 1tb and 2x 2tb drives in the enclosure and setting up a RAID 1. Would it work with those drives to get 3tb of actual storage (ignoring the real formatted capacity for a second) from those drives in RAID1. or do all drives in a RAID 1 set have to be the same size? It's got me a bit confused.