I run an Associated B6.1DL on my local carpet track. Has the brands gear diff in the transmission, while the kits ball diff is unbuilt and in the parts box. Speaking of parts, the kit box is full of spares that I picked up through Amain. The buggy runs so smooth and handles great with kit set up. Savox TG servo, HobbyWing esc and 10.5 motor, Spektrum rx.