I put 3205 miles on her on my trip to TX and I found mine gets the best mileage at 70 MPH. My best tank was 9.35 (cruise set at 70) and my worst was 7.3 (cruise set at 76 MPH) My average for the entire trip was 8.22. If I set the cruise between 65-68 it gets in the 8's. 55-65 is down in the high 7's. I never dreamed the sweet spot would be 70 but it's at that speed that it typically wont down shift on a hill. Total cost was $143x.xx RB