There is a huge thread on Pirate.
http://www.pirate4x4.com/forum/showthread.php?t=575345
I sifted through all of it and decided on the '98 Ram 2500 MC with GC proportioning valve. At the time I had stock front ('99 XJ) brakes and GC rear disc conversion. It worked well, but that was too much master cylinder. I had the nice Hawk pads, but parts house calipers. Now, I have 1/2 ton Chevy calipers at all 4 corners with a Willwood adjustable proportioning valve, and the MC is perfect. I can lock up all 4 or modulate easily, even with cheap pads.