Speed can always be a factor when you hack into the ECM and floor the accelerator.
Never buy a car that cannot be stopped by using the brakes. Which means, buy a car that doesn’t have so much power the engine can over power the brakes.
If you can floor the car then press on the brakes and stop the car and if a manual you can kill the engine or automatic you can cause it to stall and stop it is a good car, if the engine is too powerful you are at the mercy of the computer....
Of course the computer could use the ABS system to lock the brakes so you could be screwed anyways...
Manual transmission solves this problem.