Re: G-tech
I bought one when they first came out, about 4 years ago. Yeah, they're OK. A tiny bit generous on the quarter ET ridiculous on the trap speed. It gives you a 0-60MPH figure also. Also, there's an HP estimate that use the weight of the car you entered + the acceleration to give you an HP figure. You also get the braking distance from 60-0 and G figures for estimating latteral accel.
To be frank, I rarely use mine, I mean where can you make a clean 1/4 mile pass on a public highway? But like the other said, it's OK to compare your car before and after a mod...