It’s basically a low wing Telemaster. The 40 size has a balsa fuselage.
The designer came up with the name because it’s the most fun you’ll ever have with a model airplane. He may be right. A customer sent me some photos of Funsters that he and a friend have modified to look like WWII fighters, and some others on floats. If they keep building the same plane over and over, it must be good.