I have a G-tech Performance RR Acceleratormeter. You can read more on the features at gtechpro.com . Anyway I purchased this unit new a month ago, but I am not happy with it as it doesn't work well on my MR2. It works good on my Z, but I cant get a good RPM pickup with my MR2. Anyway the 1/4 time is very accurate as it shows a .01 sec difference between my drag strip run and the time on the g-tech. They are $299+shipping new, will sell for $275 shipped. I can provide you with receipt and everything, I have ALL the original equipments with the box. I would rather use the money on new tires at this point. It's a nice equipment, but kinda pricey for me. Anyway email me [email protected] if you want it