I wouldn't have any reservations about Western Digital whatsoever. I currently have 7 Western Digital Drives (5 x Internal, 2 x External) in use at the moment between my Mac and PC, having had another 2 before that (simply upgraded them as 80GB wasn't enough any more!). In addition to this, I have two friends who I introduced to WD who are running 2 each, along with a friend who uses them in his business PCs in preference to other hard drive manufacturers and has yet to have one fail.
Add that to the fact WD offer very generous warranties on their drives (3 to 5 years), and that they're very quiet, I wouldn't be worried at all, in fact I'd be happy you have one!