G-Tech is fine for what it is and if you understand what it is. A G-Tech is not completely accurate, but it is consistant. So if you run say a 16.7 at 82 mph (trying to relate to you import guys ), do some mods, then run a 16.5 at 84 mph, those numbers may not be accurate, but you can bet that you have picked up ET and MPH. So for $130 new, don't bitch.