If you can maintain constant speeds it would be but the only places I drive in that range is in cities where I'm stopping and starting a lot so the wasted energ

If you can maintain constant speeds it would be but the only places I drive in that range is in cities where I'm stopping and starting a lot so the wasted energy there dominates. I keep rough track of my mpg each time I fill up (as a sanity check to the calculated MPG my car gives me) and when I take long trips home I easily hit 33-34 mpg while weeks where its mostly short trips in the city I usually get more around 28 or lower. And those long trips sit at 60-70 for an hour or more at a time in good traffic.