I've been building PC's for the last 20 years, and I _rarely_ had a problem with hard drives failing.
I built a Ubuntu linux fox with two 3ware raid controllers to function as a network media server.
I created 2 arrays, one composed of five 320 gig Western Digital drives (plus a hot spare), and one composed of five 500 gig Seagate drives (plus a hot spare).
Over the last year I've had three WD's and two Seagates fail. I finally figured out...