I use a 2TB Buffalo NAS (actually 2x2TB but I use mirrored raid so it's only 2TB). Recently one the drives went south. Popped it out, moved drive 2 to drive 1 bay and inserted new drive into dive 2 bay. By the next morning the mirroring was complete.
 
I just hope both drives don't ever go at once. I only have 64GB left of free space. I'd hate to lose all that data.

you can try these device these are working fine Asrock X58 Extreme3, I7-950, 12G ram
OCZ Vertx3 120, Vertex2 90, WDM 1T .