That's great if all you want to do is run the ground
If you do any actual airboating, you'll have to be real careful because you won't have much throttle response that you'll need to keep from sinking if you encounter unexpected waves, wakes, stumps etc etc.... or either you'll use a whole lot of nitrous
Or for under 1700 bucks, you can put a 72" Q Series Sensenich prop and set it to turn about 3000 RPM max. That will also give you plenty of throttle response, and it will also be quieter than a lot of propellers out there.
That and frog spit, and a 2 gallon bucket with a bottle of dish soap in it. Next best thing to a gear box!