with the 6th cell conversion you have alot more power on the wheels making it possible to enertia drift, or brake slide with much more ezz. i have yet to add nimh batteries so im doing this with standard alkaline batteries, the nimh have a higher current so should be even better.
I have the supra with Stage II yellow engine, AWD, stock tires and I can drift all day. Secret is to put some weight on the back end of the car. I put a large washer against the rear bumper and attached it with a hot glue gun. Works great.