They tested it with drives up to 750GB.
1TB drives didn't exist till recently.
I just bought an e-Sata / USB external enclosure (drive interface is SATA) to hold a 3.5" harddrive (that I bought seperate). Odd thing is a lot of the enclosures I came by specifed they can only hold hardrives up to a certain capicity (ie: harddrives up to 400GB). After I bought mine I found out (from the manufacture's website) that it can only hold HD's that have a capicity lessthen 750GB - well I bout a Terabyte HD. So far it works and works well
My Question: Why the limit ?