If they are tight post-flop and no one else has called it's not good. If the board hits you strong it's less likely to have hit them.

If they are tight pre-flop and you can put them on a high pocket pair it's +eV because your hand is very easy to play.

If they're short stacked it is more likely to be -eV.

If they won't lay down TPTK post-flop it's +++eV.

It also helps if you are able to win pots without hitting your hand (using your position).