This is what the OS Max .10's looked like with the exhaust extensions. The little .10's would fly the model Ok, but not with the power reserve I usually like in a model. The original .32's way overpowered the model and almost lost it due to all the vibration...and the covering that started to remove itself while flying. The wings are not built up strong enough to hold that much power, especially with the outboard nacelles mounted so far out on the wing. The four .15's should be perfect.