They also seem to lack the fine detail that has gone into the design of the 1/8 kits. They don't look quite homemade, but I'm thinking a cross between a quality 1/8 kit and a homemade. I think they have a lot more evolution to go through.
I'm sure they would be plenty of fun though... personally I'm wondering how they jump... probably not too high since they are pretty beasty things.