For some reason the hand history converter isn't working very well, so I decided to post the text version.

UTG is an aggressive guy, running about 34/26/15 in ~500 hands.  He's been commenting on how terrible and nitty everybody was in chat too.  Flop cbet 80-85%, but turn and river cbets were much lower (35-40%) once called.  I was running 27/17/5 or something.

Anyway, here's the hand:

CO: €55.88

BTN: €59.59

SB: €42.75

Hero (BB): €120.94

UTG: €165.97

SB posts SB €0.25, Hero posts BB €0.50

Pre Flop: (pot: €0.75) Hero has Jc Ac As Kd

UTG raises to €1.75, fold, fold, fold, Hero raises to €5.50, UTG calls €3.75

Pretty standard 3bet I guess.  We're 240bb deep, but I have a premium AAxx and want to build the pot.

Flop : (€11.25, 2 players) 2c 6h 3d

Hero checks, UTG bets €7.87, Hero calls €7.87

I decided to check call.  First off, this board misses both of our ranges.  He probably can't have too many sets or 54 in his UTG open/flat 3b range.  However, I can't have those either, and if I bet and get flatted/raised my life is gonna be a bit ugly.  With the backdoor NFD too, I thought my hand is good enough to x/c flop and maybe lots of turns too.

Turn : (€26.99, 2 players) 2d

Hero checks, UTG bets €19.50, Hero calls €19.50

Again, this card doesn't do me much harm unless he boated up, and he has few combos of them.  At the same time, I could see him bluffing/value betting with weaker overpairs (JJ-KK), as well as semi-bluffing with some diamonds and 55/44 blockers, who knows.  I thought I could check call here once more.

River : (€65.99, 2 players) Th

Hero checks, UTG bets €57.50, Hero ??

On one hand he's repping a narrow range.  I'm not sure if he will vbet 2x like this, although there won't be many 2x that aren't boats, and he probably doesn't have enough 2x to start with anyway.  That aside I'm looking at 54+ and bluffs.  What kinds of bluffs he can have, I don't know, but I think he can be bluffing quite often because my hand is kinda face up.  However, I'm not sure if he will turn overpairs into a bluff anymore (he will check back a decent amount of time), and if he doesn't turn them into a bluff he just doesn't have enough bluffs.

Thoughts?  Would you play earlier streets differently, and if so, why?