No intent to burst any bubbles. My brother-in-law had the assigned task at GM's Tech Center (Warren MI) a couple years ago to dyno run every kind of spark plug they could find, the fancy expensive newfangled "U" grove, split tip, multi platinum.... the list goes on and on. They pulled 100s of loads on a bunch of motors. If they do anything, it does not show up on the dyno, not even a tiny bit. The purpose of the testing was to provide engineering with data to decide if a certain spark plug would improve efficiency enough to include that particular plug as OEM, or incorporate its design into an new OEM ACDelco plug. They weren't looking for just more power, that was only the part he was working on. They were looking for burn efficiency as well (emissions and potential fuel economy).
The results....... the envelope please..... the super duper special plugs are nothing but a marketing ploy.
Materials are important to longevity and reliability, but a spark plug is a spark plug.
Personally, in an I5, I would run nothing but OEM because of the high intensity spark from the coil on plug packs can chew up lesser electrodes (E3s for example).
