I took a good look at one yesterday. They are made of that hard cheap plastic.
The package had it so strapped in I couldn't check suspension movement, but it looks limited. The tires are not totally hard, but they are made of some sort of super Slide material. A good buggy wouldn't even be able to take off with out melting them. It has the strangest fuel top I've seen. Looks easy but leaky. The Exhaust is oval where it comes out of the engine. it is an inch across, right at the head. The carb has a rolling brass piece and not a slider. It rolls to expose a hole smaller than the Carb barrel.
The glow plug looks top notch . haha
It comes with lots of stuff, and probably isnt a bad way to get into nitro... Definately throw away once its worn out.