Adrian, the M04 (RWD) and the M03 (FWD) have the same gear set, but the M04 can run a 21t pinion, and the M03 can only use a 20T pinion. with that being said the RWD comes out of the corner harder when it is set up right, the FWD keeps a slight better corner speed. At TCS nationals, the 2 cars were very very close in speed with the same size tires. My M04 turned a 18.20 lap, and the fastest I saw from an M03 was a 18.16 I will add that I did nothing but break in my black can for about 5 minutes in water. I know that many of the fast guys were playing with motor zappers. so I'm not sure if it is a fair comparison.
And the one car that I know was fast had about 500 rpm more than me at 2v