If you want information regarding "bottom" snare mics, it should come from someone else, because I do not like them.
The best snare mic is one backed away from the snare...the farther back you get, the better the snare can sound. But of course, then the more the other drums will blend into that one mic.
Many, including me, like to use one (or maybe two) mics on *the drum kit*...this includes the snare of course. But the drummer will have to be good enough to balance the kit.
I was referring to using the pencil condenser as a (fairly at least) close snare mic on the top side, in the oft-used individual drum mic'ing technique.