On the subject of MC012 quality control: I have a pair of 012s that I bought from Guitar Satan (this occurred before I knew of this web site, and before I knew of The Sound Room). Good mics, very useful for a lot of things, but with one minor foible: one is wired pin 2 hot and one is wired pin 3 hot. I listened to them individually to make sure that I wasn't getting a duff mic body, but (more fool me- picking up mics in a hurry before a gig) I didn't hang them on a pair stand and listen to them both at once, nor did it occur to me that I might need to check their phase. Right- let's hear the chorus of "you dumb fuck!", starting now...
First outing the day I bought 'em, I hung 'em on an X-Y mount in front of an acapella quartet, and all I can say is "Bitter beer face!". Terrible. Luckily, I still keep a couple of ancient 2/3 swap cables in my toolbox, and all was well. Coulda knocked me over with a feather, but now I know better: never freakin' assume _anything_.
I may get another pair from the Sound Room to use as a proper pair (and get the M1/M3 capsules for 'em as well), and relegate the original two to other uses, like overheads, hammering nails into the wall, and such. Anyhow, the pin-3-hot one now has zebra stripes on the body in black electrical tape, so I can tell which one to use the swap on (until I dig into it and fix it, which time hasn't permitted just yet).
It sent me back to the old Gold Line box to do an absolute phase check on all my mics, anyway, so some good came out of it...