Improving gas mileage

Does anyone have any first hand knowledge of the efficacy of a device called the Vortec Cyclone? I have found conflicting information on the web about this device. With its 120 day money back quarantee from the manufacturer, it seems to be worth checking out, but I am skeptical as to whether I should go for it. Thanks.

It is NOT worth checking out. It is a SCAM. Waste your money if you want.

You’ll have a hard time finding any intelligent auto-savvy person who would waste his money on obvious junk. These things are worthless.

Scam, scam, scam, and highway robbery!!!

Actually, this gizmo DOES affect fuel economy and horsepower. It reduces both.

http://www.popularmechanics.com/automotive/new_cars/1802932.html