Potentially huge pot in a live NL game.

[flytrap]

Great NL game at Greektown in Detroit. Blinds are 2-2-5, with 2 on the button. I have about $1550 to start the hand.
I'm dealt J [img]/images/graemlins/spade.gif[/img]J [img]/images/graemlins/club.gif[/img] in the CO. A bunch of calls to me, I make it $55 to go. A lady to my left calls cold, meaning she either has a decent pair or an ak type hand. She has about $500. UTG who is very loose, but doesn't limp re-raise from what I've seen, makes it $155 to go. He has over $3000 in chips. Right now I have him pegged for AA, and maybe KK. I call, planning to play for a set. The flop is the most beautiful thing I've ever seen, J [img]/images/graemlins/diamond.gif[/img]9 [img]/images/graemlins/club.gif[/img]9 [img]/images/graemlins/spade.gif[/img] and the LAG bets $300. Do I move in on the flop, or let him bet again on the turn?