I would agree with lil-bump. Best way to put it would be: Whatever you were going to use the 357 for, put the 9100s in that spot. Wherever you were going to use the 358, you could use the 9100s or the 9100t. If speed is more important go with the 9100s, if torque, then 9100t. I chose the 9100t for the steering in my truggy because those things are so darn heavy with big tires.