Yesterday, I drove 54 miles to work and got an indicated 45 MPG overall. I did not even used the Marvel Mystery Oil (MMO) and did not drive below the speed limit all the time. I did, however, draft a truck for about 20% of the way and drove at below 60 mph about 60% of the way, using cruise control some of the time.
The engine was cold when I started, which didn't help and there was a little bit of traffic. But using my techniques for maximizing fuel economy helped me achieve pretty impressive mileage. On the way back I drove faster and hit pretty bad traffic so the same 54 miles were covered in 1.5 hours instead of 55 minutes. And I used air conditioning all the way, since outside temperature was in the 80s. Still, I got almost 37 MPG.