Interstate vs. State Hwy. 100 mile trip We have a 100 mile trip (each way) we make every month or so to pick up or drop off our son at UF, I have read that the "sweet spot" for highway travel is 71 mph in the V (?). As an alternative to the interstate route, I could take the state highway system which is more scenic, but adds about 25 minutes each way, and includes a number of red lights with a mostly 65 mph speed limit. My question is will my gas mileage be better taking the road less traveled? Or, is a constant cruise at 71mph my best bet. I really don't mind the extra travel time. Thanks in advance.