The flop is a bit ragged and everyone checked so I think it may have missed them all. You could even be best here and with position and 6 reasonable outs in a rather large pot. There is a lot of potential for this flop to develop into something dangerous, so if you're going to continue I think you want to bet. It's also great if anyone folds, because everyone will have outs to beat you and you're only drawing to top pair. I think a bet pays off.

It seems that if you do check you would plan to fold to any bet on the turn.