husng - preflop minraisers - contemplating 4-bet

[Nichomacheo]

villain has been min 3betting me fairly often now. he's a bit loose postflop. i never fold to these (in position + good odds = bad fold), but i'm wondering whether I should be 4-betting or not. normally, if I call and whiff the flop, I'll fold to a bet. seems like taking back in the initiative is better. thoughts?

Stacks are 1500/1500 with 10/20 blinds
Hero has A[img]/images/graemlins/diamond.gif[/img]6[img]/images/graemlins/heart.gif[/img]

Hero raises 40 to 60
Villain raises 40 to 100

Time for a 4-bet? If you say no, what if I had AT?