Which plugs are best for performance?

just curious on what everyones take is. Ive read some things on the internet that suggest nickel and platinum coated tips on spark plugs actually conduct better than iridium.

All the plugs im seeing are copper core but just coated with nickel, platinum or iridium. So which is best? The iridiums should last longer than the nickels but is there really a difference in performance between the two?

I change plugs in my 340 every two years because its cheap and why not. Just was trying to figure it out.