Simple testing

I am not asking for a full driving simulator along with a giant terrain full of roads and trees if that is what you thought when you first read the title. What I am asking is whether it will be possible to make some sort of way to test your vehicle prototypes and final products. Something like a rolling road that will allow you to accelerate and brake the car and change the gears showing you revs, speed, current fuel economy etc. The rolling road like real testing ones will make forces that simulate friction and air resistance at the speed that the car is travelling and therefore giving realistic fuel economy results and throttle needed etc.
Opinions?
Opinions?