Shane, on the water quenching, keep in mind that a bearing has a much different geometry, purpose/function than a knife blade, no thermal gradients, just the outside and the inside. Also, 52100 tends to be "clean" steel alloyed for a fine grain, as far as I know,... so it can probably handle higher quench speeds, but whether or not they would be any better, or worth the risk is the question.
I've heard everything from water to slow oil on it, but think a slower oil might be safest until you get some experience with it.
If you want to try and go the low budget route, I've heard people say that vet grade mineral oil works O.K. and should have similar speed to an unaccelerated quench oil. Or, maybe even room temp., canola with an interrupted quench.
At any rate, I'm not an expert on 52100, and I don't use it much at all, but I know some them that do use Texaco A.
What I’m thinking, based on what I’ve read, is that the exact quench speed may not be as much of an issue as other factors,… temps., times, heating atmosphere, geometry etc.
Good luck and I hope whatever you decide works out for you.
... It is an interesting, enigmatic and unique steel, and I'm sure there are things we could learn from it that apply across the board.
I don't think you'll find too many "definitive" answers... just lots of literature and opinions, like looking at reflections off a ball bearing from different angles.
just thought it was interesting considering we are talking about using a quench slow enough to still be under the pearlite nose and less stressful on the steel and hopefully less micro fracturing