Designing a Heavyweight

[Eventorizon]

While we are on the subject of HW's, what ESC would you use to control the massive Ampflow A40-300's? [Link: http://www.robotmarketplace.com/products/0-A40-300.html
I would be over volting the 24V them to 36V, possibly even 48V if people think the motors can cope. First thought is a Dual channel RoboteQ of some kind, but what ampage is suitable? The motors say 340A stall but you never want to give them that power else they will just burn out, so is it best to go with the 150A Dual or can you save a bit of money and go with the 120A version?
[Link 120A: http://www.robotmarketplace.com/prod...Q-HDC2472.html
[Link 150A: http://www.robotmarketplace.com/prod...Q-HDC2450.html