It's amazing....I used the mpg thingy and kept my speed to 60-65 mph. I better judged lights when stopping and I drove to brooklyn and back....about 100 miles. On the way there I got 37 mpg. Figuring this can't be right I wanted to see what I got on the way back. Several hours later I left my friends place and drove back. this time there was an accident on the BQE and some normal traffic elsewhere. This is what I got on my return trip. As you can see driving with fuel econ in mind and this nifty MFI trick!