anyone who has used this , does it really work, they have it on thunderracing.com website. but i wanna see if this thing really helps, or gives out an accurate reading, and what exactly it does do for you, as far as options

 

was going to post the same myself. im curious to its accuracy also.

 

I use the g-tech all the time. In fact just got done running with it. I love it and it's within hundredth at the 1/4 mile track. Although there is a link on this forum of another one that is cheaper then the g-tech. It sounds pretty good as well. If you spin your tires on the launch the mph will be higher. But the times are very close to track times. And yes wind is a factor. Do not run when it is windy or you will pull slower times,but you will run slower times at the track as well. I ran 3 runs with mine tonight and ran as follows. 13.412,13.424,13.470 keeping in mind when I run I run the same road same place same direction every time. It is a good thing if you want to find out if you have gained any from adding anything to your car. there are some people who do not like them, but I love mine, Let me know if I can help out with anything and good luck..