It's really easy to make a graph say what you want it to say. Selling a PERCIEVED increase in HP is also very easy. I'd like to see a product where the increase is actually documented and veirified....... Remember the engineers at MB may have designened the stock chip for a reason, and while the chip cannot increase air flow, it can change fuel and timing and possibly ignore the knock sensor which when combined with advancing the timing will result in shorter engine life and possible early failure. I'm not convinced that taking a chance on a non factory chip is a wise idea if you plan on keeping your xfire for more than 50,000 miles. ........Just my .02