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In my experience, the gyro will only be helpfull when lack of grip is a concern, being on carpet at moderate speed or RCP at very high speed. The best way to see the gyro action is to drive on wooden floor or tiles. There you will see the rear wheels loose grip and the car instantly correct its trajectory to return in line. I was amazed when I saw this for the first time, a quick correction jump, just like a slotcar returning to its course after the guide has reached its rotation limit in a curve, if you see what I mean.
In normal race with the gyro, what I feel when cornering at high speed is some massive understeering but as soon as I release the throttle the car will turn frankly into the curve, or even oversteer if the front tires are soft enough. I don't feel any sort of correction on the throttle, only understeering like if the car was saying, "OK slow down now so we can turn". Remember that when the gyro enters in action it means that your car was already out of the line, so the same situation without the gyro would equal to spinning out (or countersteer if you are fast enough). This gives a very confident driving but I don't think it would be something the beginner would apprehend easily. The beginner would either go straight to the barrier due to the understeer or to the inside barrier because he was suddenly to slow. The amount of correction of the gyro has to be controlled with the throttle while it affects the steering, very strange indeed

I think the gyro will only control the steering, I may be wrong, but I never felt any loss of response with the throttle, either when entering or getting out of a curve or doing donuts.
If the gyro was transposed to the Mini-Z it may probably require a separated racing class.