Where in SA are you ???
Popular cars with the best support is Losi and Caster in KZN.
Up in JHB the popular cars are Hong Nor, AE, Haboa which are supported ok.
There are other brands but support is questionable.
I can suggest the Caster 1.5R and its just as good as any cars running and is currently leading the KZN regional championship, so its capable.
email me and i can give you more info.
razzor@wbs dot co dot za