I've heard of a lot of trouble with the 3 TB Seagate drives. I've had 3 WD Red 3 TB drives going for about 18 months, 6 x 4 TB Reds for just under a year, and 3 x 2 TB disks (two Seagate Barracudas, one Hitachi Deskstar) for a little under three years. No failures in that time. The WD disks have mostly been under 40 C, but I can't say the same about the 2 TB disks.