AQo

id say check fold

On this board almost 60% of our range for 3-betting a CO open on the turn is a Pair of 8's or better.

Becasue of this there's very little reason to be betting AQ on the turn and this is where the idea of "charging a draw" begins to fall apart. A draw isn't going anywhere, could easily blow you off your hand and not much better is folding.

I'm not actually against turning our worst A-High's into bluffs on teh turn to try and get rid of better A-High's and pocket pairs on the river but AQ is just in no-man's land and has draws of it's own so personally I think x/c'ing the turn is probably ok and makes it easier to play the river without giving your hand completely away.

Given the pot size on the river it then becomes about your opponent. If you believe since you've shown weakness he's capable of bluffing A-High then you have to call becasue you're at the top of your turn check/calling range which hasn't hit a flush.

If you think he's a predictable TAG who is only going to bet the river with better hands then go with your read but pretty sure for the sake of your range if you're unsure you have to call down.