ive done that way to much i purposely use cruise control because i dont trust it to go into missile mode! the best way i found to get a feel for it is if you read out the numbers (to your passenger) as you go ie 10 20 30 40 50, tbh though you'l struggle to get the first few out your mouth in time when i did it i had to say, 20, 50, 60, 70 my passenger leant over to check in disbelief