Some people think more teeth is more efficient, and larger gears will have more flywheel effect. Given the relative size of the gears, I doubt you would notice either. Practically speaking, it slightly alters your weight distribution by moving your motor position. Don't know how that affects off road cars, but the current thinking in pan car is to use the largest gears possible to move the motor as far forward as possible. This decreases the lever effect of the motor on the suspension.