[soah]

That turn bet is pretty sick.

I'm thinking I might block the river... if he's sorta loose/passive you can hope for AJ/etc to call another $150 or something. The Q is a pretty terrible river card though.

Checking and calling a small bet is also an option. If he's passive he probably won't launch a big bluff and you can make the laydown if he bets big (but I'd feel better about it if the turn bet had been more like $150).

I guess it depends on the specifics of your read... 8.5% preflop raise doesn't seem all that passive IMO. It really seems like he would have raised by now if he had you beat, so it would really help to know a bit more about him to help put him on a range of hands.