Re: Secondary kick mic ....
+1 on the e902 .... I've been carrying one since the year they came out, hundreds of gigs and it's still treating me well. At the time I bought it, the D6 was becoming super popular, but never really grew on me quite as much (compared to the 902). Over the years it's been a great mic to carry for me, as most walk-on's I go to will have one or more of the usual suspects on hand (D6, B52, 91, RE20)... so it's nice to have another option in my bag.
I've never had any reason to dislike the D112, it's a useable mic for sure. I also carried a D3400 by AKG until recently, which is a great kick or floor-tom mic that can be had for very little money used. The issue I do have with both of these mics though, is the crap-tastic mounting designs. The D112 is a clumsy mic to get positioned, especially in a (small hole) ported drum, it's just too awkward to get into place with the mounting end and cable exit extending so far out the bottom. The D3400 has an integrated mount, but if you're mounting it on a typical stand, the mount allows the mic to angle from 0deg (horizontal) to 90deg (vertical) pointing towards the ceiling. I used to keep a 6" black gooseneck screwed into mine permanently, just to be able to get it into position.
I do believe that they are re-issuing the original square D12 (AKG) ... which should be interesting to try, if it's not already out there. The e902 won't be leaving my bag anytime soon though.
Steve.