Premium is simply a cleaner Fuel, the downturn of this is you do slightly loose on performance, but enough that the average person will notice.

I have always used premium in my car, and my injectors and block are sparkling.

It depends what you want out of your car, if you want to see how fast and quick you can get it to go fast, then do super.

If you want your engine to last longer then do premium (it's also recommended that if you use Super, to fill it with premium every 4th fill or so) cleans out the gunk

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