The E60 M5 had MPG of 11 / 17. Common sense would tell you the only way to get a combined MPG of ~24 for the F10 is high teens for city and >24 for the highway. That is a lot more than just 1 or 2 MPG improvement. Oh, and the F10 5 series have a 21 gallon tank, whereas the E60 have a 18.5.
I'm excited about the power and efficiency of this beast. My measly E60 550i does 15 / 23 MPG.
