So I have been looking at used xfires. Living in Chicago I think it might end up being a bad idea, the winters here get harsh, but you only live once.

So being that the US and Chicago specifically is being gouged with the cost of gas (+/-.40 swings of price in a days time). I noticed that the MPG on the '04 is better than the '05 and up models. Is this an error (kbb.com) or is there something fundamentally different between the years.

Thanks!