How much would you pay.....

I'm really think'n on a GTECH - Pro SS and a back road. From what I see in the reviews are when onboard at the drag ways they are within a 100th of a second to the actual ET slip
A big problem could arise in case a cop wanders off the beaten path (ask how I know) and the fact that the street has no traction if your making big/bigger power levels. G-techs are accurate, but hard to simulate a 1/4 mile drag strip on the street, but great for tuning to see if you got faster or slower, just keep the top speeds down.