I just picked up a 2006 Crossfire Coupe yesterday with less than 30,000 miles and immediately noticed when I went to put fuel in that it said "Use Premium Fuel Only"! I happened to be down in southern Illinois and they had premium so I did pay the price and used it. I downloaded the manual and it stated to use an octane of 91. My problem, except for the price, is that in my area (SE Iowa) I have never seen premium for sale. They used to sell 87 and 89 (the 89 was the common 10% ethanol) but now both fuels (regular and ethanol) are labeled 87 so this Crossfire is going to have to use an octane of 87.

What do most of you use and can I expect any problems with 87 octane?