I didn't read all the posts here so maybe I'm repeating something. If not, here is my evaluation of what the SB does. It makes the throttle more linear. Before the SB when the pedal is depressed there would be a little response, hit the gas harder a little more response. I never knew just how hard to hit the gas to get the response I wanted. With the SB I now know. From a dead stop a very little bit of gas gives much better response than before. If I want to accelerate a little faster, now I know just how hard to hit the pedal to get the needed response.

It doesn't make the car faster, just much more predictable.