Trying to bluff my way out of yet another tough spot

[Kirkrrr]

This always gets to me - players in position with disguised hands who refuse to make the bet on the river if they missed their draw when their opponents are obviously weak and probably would not call (1/2xPot bet would give perfect odds on the bluff). So on to the hand...

As always, 2/3 NL at Ocean'11. My opponent is a little weird - he overplays his big hands (have never seen him push all in without literally the mortal nuts), doesn't bet his draws, and rarely makes big moves, but has been caught bluffing at dangerous boards where he bet 100 into a 130 Pot in position on the river, got check-raised All-in for 115... and folded. All in all, he is not very tricky, though. He's got about 600, I got him covered. My image is very aggressive but I haven't sucked out on anyone in quite a while so for the most part my bets are respected.

I'm on Button and look down at 5 [img]/images/graemlins/diamond.gif[/img] 6 [img]/images/graemlins/diamond.gif[/img].
UGT (Villain) calls, UTG+1 calls, 3 folds, MP2 calls, I raise it to 15 (my standard open-raise), Villain calls (as he always does if he already limped in), UTG+1 calls, all else fold.

Flop: 3 [img]/images/graemlins/club.gif[/img] 4 [img]/images/graemlins/spade.gif[/img] Q [img]/images/graemlins/heart.gif[/img] (Pot - 50'ish)
Check, check, I bet 40, UTG announces "i already got trips, don't know what you got," and calls, UTG+1 calls.

Turn: Q [img]/images/graemlins/club.gif[/img] (170)
UTG bets 50, UTG+1 folds, I call.

River: A [img]/images/graemlins/diamond.gif[/img]

He looks at me, asks "You got pocket Aces?" and checks.
I bet 150...

Comments?

Kirk