I personally use 93 not because it gives me more power but because it burns cleaner, often people just talk about how a car doesnt need higher octane fuel becaue if your car was designed to run on 87 there is no chance of premature combustion if u stick with 87 so why go higher, this is true, but premium fuels also have a better composition and thus can burn cleaner and contain more energy.

Its only 10 cents more per gallon, if it was .40 i doubt i would keep using it.