[99LeCouch]

Any engine damage will cost more. And, the difference in performance on a turbocharged or high-compression naturally-aspirated engine might well be worth the premium.

Another difference is that the systems designed to prevent damage are reactive instead of proactive. Sure the knock sensor will cut timing, but engine damage might already have occurred from the knock it sensed.

Using premium in a car that calls for it is a proactive way to prevent damage.