Pretty good but could be better
Opening the box, my first thought was that this looks like a high quality piece. I was disappointed that the instructions were essentially useless (although mostly unnecessary) and had to figure out how to make it fit a 2007 Envoy. An extra hole about 1" diameter has to be cut in the housing to connect the hose that was part of the original configuration. The throttle feels a little more responsive and there is a minimal increase in fuel mileage (.5 to 1 mpg depending on conditions).