AJs - good or bad steal - 6 handed

Pacific Poker
2.50 + .50 buyin, 20 person NL

Down to 6 players.
Blinds are 50/100, going to 75/150 in about 2 minutes

Hero has about T1000 chips
rest of the table is similar, except for one big stack with about 3000

Hero is dealt: A[img]/images/graemlins/spade.gif[/img]J[img]/images/graemlins/spade.gif[/img] on the button

UTG (big stack) calls $100
MP1 calls $100
MP2 calls $100
Hero pushes all in for $1000

Too aggressive? Look ok?

With the blinds, there was about 450 in the pot, about 1/2 my stack.