I think its a great transaction. The power train in there was built to handle a lot more than the engine ever dreamed it could deliver. Consequently It will last a long time if maintained. Parts are readily available. It will go 40 mph all day long.

I cant see the seat support in yours. They did come with a spring setup. Also, Walk's is reproducing the spring seat. That might help the ride even more. The tallest tires you can fit will aid in the speed and the ride. These things all came with a very deep axle ratio. You can literally keep putting diameter in there till you hit something! The tire will start to hit the frame on turns.