I have exactly your setup, revo with hybrid buggy diff, gear 16/38 with Neu 1515 1y,MM controler and Flightpower 4s, and i'am in love with this setup. Lot of torque, very good top speed, about 35m/h and can gear higer without any problem to reach about 40.

I've zero cogging with my Neu/MM setup gear on 16/38.

Next sumer, i'am plan to go to 5s, gear 16/36.

Good luck