Re-Volt has different demo versions which have different, unique R/C cars only available in each version (and not available in the full version). I would like to try those unique cars.
Example of a unique car in a demo version ('Gamespot' demo version):

The car at the right is the unique "Gamespot" car.
Here are the unique cars and the demo versions that I'm looking for:
Demo name — Version — Unique Car
PCXL (PC Accelerator) — v0.01pcxl — PC Accelerator (grey, based on the 'Aquasonic' R/C car)
RIVATNT2 (Nvidia Corp) — v0.01nvidia — RIVATNT2 (green or blue, based on the 'Aquasonic' R/C car)
Gamecenter — v0.01gamecenter — Gamecenter (red, based on the 'Aquasonic' R/C car)
Creative (Creative Labs Ltd.) — v0.01creativelabs — unknown
McDonalds (Ziff Davis Media) — v0.01ziffdavis — unknown
Note: The Re-Volt Wiki lists some of the demo versions, but it is incomplete.
I'm looking to get the unique RC cars ony available in the demo versions - how can I do this, or can anyone point me to where I can get these demo versions?