Thanks for the advice Carb
I like the DEX: I have a 2009 model as a shelfer from back when I was still collecting RCs - I was going to sell it, but it's market value is too low.
Anyway, I'm looking for a car with belt drive that can both take ball diffs and gear diffs - which narrows the choice down considerably
I've always liked Schumacher's different approach in the construction - hence why I'm more interested in that than a TRF.