[BenA]

I think I misunderstood the question. I didn't realize it was if you limped and it was raised back to you. I that case, always call one more. If its 2 bets, its a matter of pot and implied odds against you hitting your set. For instance, if you limp EP, the player to your immediate left raises, its cold called by 3 and 3-bet by the button and the blinds fold... you may safely assume that all cold callers will at least call one more, so you are getting something like 13:2. Not good enough for a set, but if these people will keep giving action, may be good enough to play. However, the chance of it being capped behind you by the original raiser is a serious consideration, and this also becomes very read dependant. If its two back to me and the pot is still small and I'm OOP, I generally fold 77, but as always, there are exceptions.