RE: Tamiya JS-2 question
You get metal lower hull, drive sprockets, idler wheels, suspension arms and brackets, steel torsion bars and Tamiya's well proven transmission systems in addition to the complete DMD/TO drive and sound system. Some after market parts are coming on line, should be available in a couple months if not less.
The prototype tank was quite crude to begin with and didn't have a lot of odds and ends hanging on it.