going from a bosch second gen performance speed to the 4th gen speed day to day use has not added a huge amount to the experience. I can climb faster especially on steep hills. . like the second gen would hit the peak power when I put out 450 watts or a bit less. the new one is about 520 watts. I never run out of torque now unless its a really steel hill around 22%I thought the small chainring sucked but I got about 12,000 miles on it I only got 4300 or two chains on the regular. size.