After about 20-30 seconds these are the measurements I got some time ago for the Hacker B50-18S in the JePe carbon fan:

16 x CP 1700 cells -> 590 Watts 40A

16 x GP 3300 cells -> 790 Watts 44A

18 x CP 1700 cells -> 760 Watts 40A

18 x GP 3300 cells -> 910 Watts 50A

20 x CP 1700 cells -> 940 Watts 44A

20 x GP 3300 cells -> 1100 Watts 56A

The measurements were made over two years so there's some variation in battery state, when the measurement was taken, etc. As usual the GP's hold the voltage much better than the CP's. 20 GP cells is probably over the limit

...

The JePe and Midifan have comparable measured efficiencies, the DS-51 does slightly better esp. the new one.