How would you play this?

[Banker Ace]

Here is a situation I occasionally get myself into, where I don't know the best move. I limp from middle position w/ medium suited connectors (ie. 67s). The flop comes down A45, giving me the open ended straight draw. Do I check to the late position limper or bet 1/2 or pot-sized?
-If I limp, I may see a free card, I may call a small bet, or I may have to fold to a pot sized bet. The oppenent would probably put me on a draw, so if I complete my straight I might not make much money.
-If I make a medium bet, he might call which would mean that if I miss the turn I will either have to put more $ in or probably drop to his steal attempt.
-Same scenario if I make a pot sized bet, however he might fold and I take the pot there.
I do realize that some of you rocks may not even play this hand from middle position, so please only respond if you would play this hand. I'm finding that at PP 25NL suited connectors and small pairs make more money than Ax. In fact I'm a slight loser w/ KK over the past 10K hands.