I decided to make a comparison thread similar to Manhunt/Manhunt 2 Vehicle Discussion, as I think it will be interesting to compare the newly uncovered beta vehicles vs their final counterparts.
I will start with Cheetah vs Rocket (or Testeros, model is same):
While shape-wise it remains almost the same, notable changes in the final version can be seen in the more detailed front window, removed front plate, replaced badges with emblems, almost completely remodeled rear, smaller rear plate, modeled exhausts and re-positioned front wheel arches. Also not limited to Rocket only, all vehicles in beta appear to be 10x smaller.
In my opinion, Rocket looks better, but only after the wheel arches are re-positioned like Cheetah's.