Hello,
I am the tech manager at Autolite spark plugs. Alot of misconceptions about iridium spark plugs on this forum. Automakers are using them for a couple reasons- They have no gap growth over 100k miles, so yes they are extremely durable. They are benefits to using them in any car. They use less voltage to fire, amek a larger flame kernal in the combustion chamber and actuall burn more of the fuel that goes through the engine.All real benefits based on technology, not gimmicks. Believe me, automakers never want to pay more for any part, when they do it is because there is a real performance benefit.