Hello; I have a Laser 100 in a Balsa USA Taube that weighs 12 pounds, it spins a 15x8 APC prop up to 8800, which is fine for me. The engine suits the Taube perfectly. I can get as much as 49 minutes out of 16 oz. of 0% fuel. This plane will fly on the idle and even gain altitude if I'm careful. I rarely go over 1/3 throttle on that plane. I blend my own fuel according to Laser's formula, costs less then $8 a galon that way.