Hi there,
Americans use a different rating sytem: AKI for them, RON for us. Their "Premium" fuel (93AKI) is pretty much our "Super Plus" (98RON).
[ame="http://en.wikipedia.org/wiki/Octane_rating"]Octane rating - Wikipedia, the free encyclopedia[/ame]
That being said, it explicitly says "98RON only" on the sticker on my fuel door.
It seems that 95RON fuel is more prone to the "cricket syndrome" (fuel pump chirping) and yes, you will probably get less power, particularly on a hot day.
