Live 25-50, big decision with bottom 2

[B-Man]

Bellagio 25-50. The game started a couple of hours earlier when Jamie Gold arrived, and 6 people (locals) at my 10-20 table immediately left to start a 25-50 with Jamie (they were practically drooling). That is higher than I usually play, but I decide to take a shot.

I have about 6,500 to start this hand, villian has about 6,000.

UTG (villain) and 5 other players limp, I call 25 with 84o in the small blind, and the BB checks.

8 players, $400 in pot.

Flop: T 8 4 (2 hearts)

I check, BB checks, UTG checks, MP (aggressive player) bets 300, the button (solid player) calls.

I make it 1,800 to go.

BB folds, then UTG instantly check-raises all in for 5,900 (4,100 more for me to call).

Everyone else folds.

Villain has been pretty agressive, but he does not seem completely crazy. My gut says that he probably has a set, or maybe top 2 pair, but I also think he could have limped UTG with AA or KK, and also could have a flush draw.

There is 8,700 in the pot, it will cost me 4,100 to call.

I am leaning toward a fold, I think for a minute or 2, then I ask villain if he wants me to call, and he looks me in the eye and says, “Absolutely.”

Your action?