I'll tell you what I don't like: the D112 mounted inside the drum via the May internal mounting system. I get a lot of click and not much body. I think it's because the mic is coupled to the shell. The mic position may be related too, but the May mount doesn't have too much range of motion.
So, use an external stand.
Most of the mics already named in this thread have great reputations and have been used on many albums and tours. Whether or not you ultimately like any of them depends on the drum, the drummer, the room, the placement, the processing, and the song. Not to muddy the waters, but that's the reality of it.
I'd recommend buying used, so you can sell the mics you don't like without losing half your investment. This is riskier with condensers, which are more sensitive, but most kick mics are dynamics. (I've seen videos of Bob Heil throwing a PR-30 on the floor to demonstrate how rugged it is.)
If you have the stomach for more research, there's a couple more kick mics nobody has mentioned. I'm cataloging them all here:
http://recordinghacks.com/microphones/tag/kick-drum
Click through to each mic to see reviews and specs.
I'm most intrigued by the Elation
KM202, although that's probably the hardest to get. The factory sells them via Ebay, but they're not common.
Oh, one last thing -- as you suggest, it's pretty common to mic a kick drum with two mics. One goes inside to capture the attack; another goes outside the front head to capture the tone. You need to be careful of phasing issues, but if that's sorted then a blend of the two might give you the sound that no single mic can. It doubles your budget of course, and consumes another mic pre and probably another input on your DAW. And the mix engineer will probably sound-replace whatever you record with a sample anyway.
But it makes single-mic shootouts harder, because ultimately you're only hearing one component of the final sound.
