Note that with a 2-disk setup, you can only have either RAID-0 (No data protection) or RAID-1 (Mirrored disk). You need 3 disks for a RAID-5 setup for proper data protection. As this appliance is for my personal backup, which doesn't clear 4TB, I opted for this 2-disk system with RAID-1 and (2) 4TB...