[MSportX1]

Teleskier, before claiming that your X1 has an issue in gas consumption, like you said, do a highway test. For city driving, it is difficult to compare the number, because San Francico and New York may get much worse city driving mpg than that driving in a small town.
As I said, mpg number is sensitive to driving style. Even in highway driving, if a person pushes gas and realases gas paddle frequently, he definitely will get worse mpg than that by another guy who keeps speed (gas paddle) constantly, even though both of them have the same average speed. So, for the test purpose, try the following things to see what is the best mpg your X1 can achieve:
(1) Find a good day that you do not need to turn on air conditioning.
(1) Find a highway that is flat and no traffic.
(3) Reset trip computer before driving. Turn off ASS (Auto Start/Stop). Do not turn on Eco Mode.
(4) Keep 60-70 mph, try not to pass anyone.
(5) Keep watching the instant mpg needle and try to maximize the instant mpg as possible as you can. Usually, if you let your foot slightly touch the paddle, you can get 35-40 mpg in the instant mpg needle display.
After test, let us know your mpg displayed by trip computer. If you can get 28 mpg and above, your car is normal. If you get 25 mpg or below, your car has a problem.