I work for a company that sells these but haven't had any feedback from customers who use it. Has anyone had positive results with higher MPG with one of these? Any negative? Thanks for the input.

I have always heard they are garbage.........

If you work for the company, how about posting up some credible test reports showing the performance or mpg gains one might expect?

If you work for the company, how about posting up some credible test reports showing the performance or mpg gains one might expect?

Works for a company that sells them, could be an Autozone...not like everyone who works there, knows how good everything is...

Good point. Thanks for the correction. I read it that he 'worked' for the company. 'My bad'. I apologize.