I recently took a 100-mile trip in my gen 2 Volt. I wanted to compare the mileage with making the same trip on my old gen 1. I was disappointed that the mileage appeared to be 54 MPGe, which is less mileage. So I did some figuring and the mileage was around 74, which is considerably better. To me, the mileage is the distance I drive divided by the amount of gas I had to buy to do it. To me MPGe is irrelevant and essentially meaningless.