I would like to have the option to see an "instant" gas mileage reading with the car. Some vehicles do this, it's not new tech. I want to see a "what's my car mpg right now" at whatever speed I'm doing. I.E.: At a stop light it would read zero mpg. At 65 mph, on the highway, it would read 38.5 mpg or so. Driving down the Cajon pass, in nuetral, at 70 mph it would read 451 mpg.