You should try to verify MPG on highway with light traffic. City local MPG can be very different on conditions.
This brand is for younger people, not for mature (or older) people. If you really care about MPG, you should buy Toyota instead but Toyota will also let you feel a little bit slow or tame too.
I calculate MPG on my cars every time I fuel up my car. My purpose is to make sure my car is still as good as new...