i think a bigger pre flop bet was called for given the number of limpers and the size of the pot. also, if you raised a more substantial amount and got called, then it would be easier for you to give your opponent credit for a stronger holding like TT (which is exactly what i put him on before i saw the answer).

as for putting an opponent on quads, i have definitely done this when i had JJ and the board was JTXTX. the guy had re-raised pre flop and capped every street against me. on the river i just called, fearing the inevitable TT, because no other raising hand made sense to me. it turns out he had ATs, phew...

ChezJ