[Piwoslaw]

My personal opinion is that each car in the EM garage should use the FE numbers for where and when it was made/bought. This means that new cars bought in the US should use the new EPA, while older cars should use the standard from a few years back, cars bought in Europe should use the European standard, etc.

Of course, this means that models offered on both sides of the pond might have totally different numbers. I doubt that a car made for the European market would get the same results in an EPA test as its American counterpart, and vice versa. Even if the engines are the same size, each will be tuned to pass different emissions regulations on different fuel, each car may be fine-tuned for a different FE testing cycle, and each may have different trim/options.