So after several dozen other "miracle" plugs that promise to give you increased horsepower (some tests show up to 37%), and mileage never before seen, whiter teeth, fresher breath, and a reduction in cavities, somebody has come up with one that actually works? Doubt it. In the pursuit of a 3% gain in mpg that costs millions to car companies, if someone actually made a plug that did anything it would be in every car made. Remember Split-fires - the plug that wold revolutionalize the world? Can you even buy them anymore? I know they had to remove the power and mileage improvement claim from their advertizing. A spark plug is a nail with an insulator around it, and of the two the insulator is the more important. If you have worn plugs and replace them - with anything - it will make a difference. So far nobody has been able to show any significant improvement over a new basic plug. Get a set that lasts more than twenty thousand miles and worry about something worthwhile.