everyone thinks it is. But I drive these things all the time. my example is the Jupiter off ramp and the results are clear.I blame the laws of physics.
Even in ordinary cars, suspension setup, the width between the tires, the type of tires, dry versus wet pavement, etc., can dramatically impact cornering speed and stability. That difference is more significant than 3 MPH. Oh, and it depends on the curve you are cornering as well.