Just wanted to add a little bit of my experience with this here.
In Jan of 2010, my front oem calipers (13WG) had a frozen pistion in each, so I swapped them out with the larger 13WH, along with the correct/larger rotors (Just required a slight modification/manipulation to the dust shield). They were replaced with the reman'd calipers from RockAuto.
Recently I noticed my braking wasn't what it should be, stopping distance had increased, and was a lot less smooth. One night after work last week, I quickly shined a light on the pads through the wheel and could see they were worn, so figured it was time to swap the pads.
This past weekend I stopped by Advanced Auto and picked up the pads, and headed home to swap'm out. When I got to pulling the calipers off, I noticed the pads weren't worn evenly, and when I went to compress the pistions, two on each caliper was frozen. Oh yay! So I reassembled everything and CAREFULLY drove to NAPA and bought the reman'd calipers there. $114 + a $50 core charge per. Went home and swapped'm out, bled the lines and can once again stop on a dime, and smoothly.
I must say too, these NAPA reman'd calipers look sooooo much better than the ones I got from RockAuto. Nice protective coating, and the materials look better as well. Here's to hoping I'll get better luck with these. I'll be doing some of the [hopefully] preventive tips I've seen floating around here as well, like greasing up the retaining pins and such every so often.