blkt2 will be here to clear things up.

Don’t think I e ever changed a plug and noticed a difference in how something ran.

Yes, surface gap plugs, I ran them in the early 70’s in a Kawasaki 500 Mach 3.

I had an old Jonson outboard that ran like crap with plugs other than champion..

My truck had a random miss at idle, new NGK plugs fixed it.

I used to race an RX-7 for a living and put in new plugs every single run. They cost $30 each and the engine uses 4 of them. There was a very noticeable difference in performance using fresh plugs. Even on daily drivers I change the plugs every 3rd oil change which I do between 3500 to 5000 miles.

Surface gap plugs are not uncommon in small engines and occasionally you will see them used in a normal car.

Resister plugs up the flash over coil voltage and are better for performance. They normally are not used on a race car for fear that the resister will fail or on on small engines that have high levels of vibration that can cause the resister to fail.

This is the old one. It runs much smoother now.

Run it and watch it...

Changed plugs on all of my last 5 vehicles at over 100,000 miles on the plugs. Zero difference in how they ran idled or fuel mileage.

Yep, the tip, just the tip.

Not sure but it works just fine. Much better than the old one.

I hotrod everything that I own including my daily work truck and I have a lead foot. The difference is very noticeable to me and plugs are cheap. The difference is much more pronounced in more demanding applications. Plugs also have a habit of chemically welding themselves to the threads in the head and I simply don't want them in there that long.

Ran those on a 1985 Black Max. My mechanics brother kept trying to get me to run the normal looking equivalent. One day when boat was in the shop he swapped them out. I noticed no difference.

Most of the difference can only be seen on an oscilloscope. They usually only use a plug like that if the engine has a very high cylinder head temperature and they want a very cold plug. Cold or hot in a spark plug means the actual physical temperature of the spark plug and not the spark that it throws. On an application that has high temps it is possible for the ground strap on the plug to get so hot that it burns away or is so hot that it becomes the point of ignition for the a/f mixture instead of the spark jumping the plugs gap.