The new Bosch drive felt punchier when it came on (sport mode) while the Yamaha (also on the highest power mode) was smoother. However, when climbing really steep hills )to the point that you would have to dismount and walk), the Yamaha pulled much harder while the Bosch would just bog down as if it had a current limiter set too low. The Yamaha seemed to pull much stronger in bigger gears (especially the big chain ring) while the Bosch pulled better when you used lower gears and your pedal cadence was higher. For myself, I preferred the Yamaha. They both seemed to produce a lot more power than the claimed 400 watts, though.