[BrianG]

On 3 cell, you should be using a UBEC. Most people may say you should be fine, but the added A draw from the fans may be overworking the MM BEC.

However, that won't help your motor temps at all. I'd look to changing gearing to fix that.

And, the way it turns left when it loses power tells me that the Spektrum needs to be recalibrated. While you bind the tx/rx, hold the throttle and steering in the position you want it to be at during failsafe. Generally, thats throttle=neutral and steering=center.