Congrats
I never drive a gas scenic.
I can achieve 50 mpg at 80 mph in our 1.9 dCi (common rail turbo diesel) but as soon as there is wind or it's hilly or it's cold, then Highway EPA (48 mpg at 75 mph) is difficult to achieve even at 68 mph.
How old is your scenic ?
In our 2001 scenic, a 12V load (20-30W computer + 50-70W coolbox) or one additional passenger is noticeable on the highway. At the opposite, on country roads the AC isn't noticeable.
Since I'm hypermiling, I prefer our old
megane classic (4 door) while my wife prefers our
scenic
Denis.