This is only a guess, and I MEAN, only a guess
Alloy wishbones mounts
Alloy shock bodies (threaded?)
CVD's all round
fully ball raced
Alloy Machine cut motor mount and cam
Slipper clutch
New Diff screw set
Improved steering arms
C/F chassis/top deck
Maybe some mods we are trying here in the UK, who knows, if they market the kit and basic components in the kit are not right, the car will flop, no point in that is there. Some of the issue's can be explained away due to the cost, but if you are going to market it against the likes of the XXX4 G+ and Yokomo, it has got to be the mutts nuts.