COLT, can't go wrong with a Colt, first makers in them. Been around for years.. Get your Colt, then look at other brands to tinker with for your second AR.
SHTF vs TEOTWAWKI you ask? SHTF, just some crap on the ceiling and walls, TEOTWAWKI end of the world as we know it. Orignally made by 9mm/®™©