TrainsRMe,
I originally got the ERR Beep Commanders to power my Beeps which also had two motors but no flywheels. I was not impressed with the "toy like" running of the units. Yoder used a much better motor and the ERR Beep Commander (that I took out of one of my Beeps) controls the motors much better. Great slow speed and throttle response as well as a bit of coasting.