Didn't he say he installed F Sport fronts. So if he installed the stock corresponding rears, why would it lead to increased rotation? wouldn't it be like driving a stock 200t/350.

IIRC the F sport does has a unique brake booster part #, but i'm not sure its to do with bias or what it does actually.. but i don't think it would be a huge difference to make things dangerous.

 

OP asked if current front rotors and calipers could be mounted in rear.

 

Yes, if you installed front brakes in the rear, I feel that would upset the balance of the braking, even if the fronts were slightly larger than the new rears. That was my question.