My favs are Hitachi and WD.
Me and my freinds have 2 xboxes with Hitachi 160gb 7200 8mb cache, one with WD 2000JB, 2 with WD 1200JB, one with WD 2500JB one with WD 800JB, and a couple with seagates and maxtors.
I have had 2 maxtor 40GB drives die in my PC (yet another one is loud as hell, and wont lock), and 2 Seagates die in my Xbox (one was the stocker, just made grinding noises one day, then always booted up w/ error 7, the other was a 2 week old 120GB, just stopped spinning up and the board was really hot).
I also have a Toshiba 80GB laptop drive (5400rpm, 16mb cache) in one of my xboxes, and it works great. It locks, is silent, and stays very cool. (after an hour of playing halo 2 off the HDD evox said the temp was 92*F)