Take a look at what people have said after having a unit installed.
My experience with CGON as a company was definitely a positive one. The installer was friendly and answered all my questions about the ezero1. I do around 40 miles a day and I am noticing an improvement in my average MPG, the car is smoother and the emissions are down. If you do a lot of miles, this is the gadget for you!
Does the car feel smoother to drive?
Does the car sound quieter?
Did you find the car to be more responsive?