CO was playing 46/23/9 over 30 hands. When he makes a small 3b I wasn't quite sure if I should 4b and get to flop with SPR=3, or just flat and play a smallish pot. I thought my AA wasn't that good to warrant a 4b here, but I might be wrong. Thoughts?

This is a spot that I find somewhat tricky. We have only one weak backdoor draw, so we'd be forced to x/f on lots of turns after calling the flop. At the same time, we are more or less at the top of our range, and folding to a single seems a bit too weak. I think this discrepancy comes from the fact that, despite having the best hand somewhat often on flop, we just can't profitably continue on many runouts.

That said, how would you play here?