Well, the xpro have some hop up the Mad Rat dont have stock/
Ball bearing
Alloy shocks
graphit/plastic spares
clear body and wing
I think but not sure, the xpro comes without tires.
The mad rat is the same car, but cheaper, with plastic crap shock, bronze bearing and painted crap body and wing.
Make your choice
You will absolutly need no hop up, but you cna buy some if you want, like alloy carriere, carbon shock tower and rear T piece etc.
With Lipo, you should put about 30g/60g on the front.