The box art is a work of art...
Manual
The parts count isn't really more than you'd expect for the price. The extra 200 yen seems to just be for the special design...
Head. Slightly revised design.
Body. Most of the outer parts are new designs.
Core fighter. Looks similar to the Guncannon version at first glance, but it's actually a new mold.
Arms use the same configuration as the GM Kai
Legs. The thighs are shared with the GM Kai, but the lower leg armor is a new design.
Weapons. The shield is the same as the GM Kai's
Bazooka. New design.