Is this kind of play optimal or simply speculative?

[FlopComesBricks]

Limit holdem:

You either limp/call a raise or cold call a raise.

You suspect your villain is on overcards such as AK, AQ etc. The flop comes rags (no paint) and you've hit a piece of the flop. Its heads up.

What do you do versus some aggression? Do you call down, raise or fold?

I find myself in this situation alot in limit. Sometimes I'm right to call/raise because they've missed overcards other times I'm punished severely because they've got an overpair.

In the "long run" whats the best play in this situation? Do they have overcards often enough for it to be profitable? Or do they have an overpair often enough where you should fold a single pair unimproved?