i used a buddy's on my car to test 1/4 times, and i didnt trust it. last time i was at the track i hooked it up again, and it was right on the money. the time slip said 14.695 @96.82 and the gtech said 14.68 @ 96.0. thats pretty damn close. i want to get one, but i rather put the $200 into making the car faster, not see how slow it is.lol