You snooze, you lose!
Seagate has sadly fallen down on the job of improving performance, quality, and value to their customers and shareholders. I have been a Seagate user for 30 years, at times a shareholder, and a consultant to the company. Unfortunately, in the past few years, they have not kept up with the competition (WD) in the hard drive arena. I had been using Seagate drives (500GB to 1.5TB drives) exclusively on my systems since I started consulting again in 2007, yet their drives run hot, generate a lot of bad sectors, and don't have adequate spare sectors to keep the drives from failing. I recently switched from Seagate to WD drives, and at the 2TB level, the WD drives run better than 20 degrees F cooler, have at least double the number of spare sectors, and don't have failed sectors nearly so often. What does that mean to me, as a small business who's systems have to run 24x365? A lot! I've had to return several of my 1.5TB Seagate drives under warranty in the past year, and none of the WD drives.
So, at this time, Western Digital drives appear to run cooler, be more reliable, and are cheaper than Seagate drives. Not a good equation for Seagate, I think... :-( FWIW, I run about 20TB worth of disc on my server/workstation as arrays and individual discs. Most are still Seagate, and I haven't had any problems with the 500GB Seagate drives, but interestinly enough, the 500GB drives (7200rpm Barracuda) have as many spare sectors as the 1.5TB (also 7200rpm Barracuda) drives, and they run 30 degrees F cooler. What's wrong with this math?