The Super Tiger GS-40 runs just fine on a 10 X 6 prop. I've had the same 10 X 6 MAS on mine mounted to a Sky Raider for 2 seasons with 6+ gallons of fuel through it and its running like a champ. If the speed is too much, you can run a 10 X 5 also, but try the 10 X 6 first.

Hogflyer