Yeah I've been in this position once but the player I was up against was a new live player and reading him was pretty easy.
Long story short: If the board pairs, play it like he made his set. Unless you can beat a set or it's a set race, you know you can get away from it. If you fill up because of the paired board, then you have to consider that he's got a pair in his hands.
So basically, every street, adjust your thinking and assuming you can and will be beat. Then just work out how likely that is and whether the player has it in them to
bluff in that position. If your answer comes a no, then reluctantly fold.
Never, as Quads are just too rare. I would rather put my opponent on higher Full House, than Quads really.
