You could also mount 2 electric motors in a push-pull (centerline) configuration that would counter out the prop torque so the boat would run more true. An electric motor configuration would probably be half the weight of the gas one so adding another motor wouldn't alter top speed either, it would probably pick up low end accelleration to boot.
Aquacraft seems to be enamored of nitro/gas performance though. Smoke, fire and noise!
Here's the one you buy if you want to do the conversion: