I do in-home computer work as a side job and have seen many computers with WD drives, and have NEVER seen one in a personal computer that did not develop bad sectors within the first year!
Also, at work we just bought 100+ computers on a bulk deal, then found out that they all included WD drives. Well, after three months, nearly half of those drives have had to be replaced due to hardware failure...
In conclusion, my recommendation is to avoid buying a Western Digital under any circumstances!!
(Having said that, I have also heard from people who swear by WD drives, but I will NOT buy one!)