I always ran my Yamaha in the top level and still got 30miles all the time with half a battery left..
But again slow rides and it was a pw, maybe a little less power than they have now?
Weight and speed makes a big difference.
Also at higher cadences pw gives less support. I have pw-se, if I stay below 20mph, I get at least %20 more range than my bosch cx on the same route.