4bet PF does define your hand, and you won't action except from loose A-K/ Q-Q, or A-A. So, a 4 bet looks like a pretty poor play. So you elect to call, which i like though i would then c/r the flop. It makes it even easier to decide if he has a hand better than your overpair since he would have to be holding something good to put in probably half his stack on the flop (something better than your overpair).

So, i say calling OOP with K-K is good, but i would go for a c/r on most flops against most players.