WonkaBalls, the B4 transmission will handle either the 1 or 2 with ease. I have the same transmisson and have run the 3-star extensively and the 4-star a few times. I also had a real hot sensorless system for a while. No transmittion problems.

R3MY, It's the opposite. The 3 and 4 are recommended for on-road, 1 and 2 for off. But, in RC, there are no rules. You can mix and match all you like.