Responding to a raise with AK

[Dr. Badhead]

I've had this situation come up several times in my last few MTTs. I'd love some feedback.

Pokerroom 30+3 MTT Final Table (everyone is ITM) BB=300 Nine players left

I have 3.2K and am a middle stack at the table in late position. The villan, who has been very aggressive but hasn't had to show down many hands, raises to 1.5K. Many would say "instapush" but I wonder if my most likely situation is a coin flip and I should wait for a better situation?