Just got my rebate from my income tax and I decided to buy some spark plugs. I went to the auto store and got some NGK Iridium IX. I installed them and took it out for a test drive. The car started to hesitate (I think that would be the best word for it) when I would push down on the accelerator really hard. Went back and talked to another guy and he said they burn too hot for my car. So I ordered some Autolites Iridium and bought a fuel filter just in case it was that. I installed the filter and that helped the car allot but didnâ€™t fix the problem. So today I got the Autolites and installed. When I took the NGK out the side electrode was completely white like it was too hot and when I finished the install I again took her for a test. WOW, what difference that made. The car runs so much better. Itâ€™s almost like sheâ€™s a new car. There is no question to this post. Itâ€™s only if someone else is having a similar problem and wondering if the NGK are good. Just to clarify, they didnâ€™t work on my 02 v6 mustang.