25/50 tough spot with TPTK : felt it or fold it?

[teddyFBI]

Hero is UTG with A [img]/images/graemlins/club.gif[/img]K [img]/images/graemlins/club.gif[/img]

Stack sizes:
Hero: 5K
Villain: 11K
SB: 2.8K

Hero raises to 175 from UTG, Villain calls from UTG+1, SB calls, rest fold.

Flop (pot: $575) : A [img]/images/graemlins/heart.gif[/img]6 [img]/images/graemlins/spade.gif[/img]2 [img]/images/graemlins/heart.gif[/img]

SB leads out for $450, hero raises to $1,400 (planning to get it all in vs. SB), but Villain behind shoves for 11K.
SB Folds.

Hero? (has $3,425 behind, pot is $7,250)

**READ: important >> Villain is quite nitty, but otherwise a pretty solid winner who has been running well vs. hero past few days. I don't see him doing this with AQ or worse...then again, I'm getting better than 2:1...