I've been racing 1/8 buggy for about 2 years and a buddy of mine has been for about 6 years. Hes had 9 different buggies (mostly ofna, but hes had 2 kyoshos and this matrix) and the cen matrix drive tran is TRASH!!!!!!!!!!!!!! He is running the RB concept S7 engine (which someone on the cen forums said was his reason for wearing out drive tran parts) and hes gone through 3 different sets rear and center diff cups along with two spur gears. We know these buggies better then we know the back of our hands and the Matrix RTR's drive tran is nothing short of junk and thats all there is to it. Its a great buggy like I said before it handles nice and everything else seems to be great quality besides the drive tran. Not to mention how tight the bearings fit in the steering knuckles... he broke one and had a hell of a time getting the original bearings out and when he tried to put new bearings into the new knuckle it fit so tight it made the bearing tighten up and start to bind. I don't know if this is the case for their kit but it sure as hell is for the RTR. You can deny that all you want but this is personal exprience and I am no newbie to this hobby.