Well, I had a little surprise a couple of days ago. About six months ago I bought a Maxtor Diamond Max 20.5 7200 intending to make it the centerpiece of my new rig. Since I need a lot of storage I just picked up a WD 60G 5400, the one with the 30G platters, to use as storage (140USD at newegg).
I just put my rig together, finally, and ran some sandra on it. The Maxtor 7200 gave me 14210, but the WD was 20940! And the WD is absolutely silent. The Max is very noisy comparatively.
Yes, I know, six months is a lot of time, but.... what can I tell you?