Completed a 6500 mile trip in my 2012 . From Nevada to southern Arizona and across Texas to Florida. The return was through Oxford, ms ( very nice place with lots of history) to St. Louis . Then across the us to Denver and Cheyenne and finally through salt lake to reno. Speeds were varied but kept up with traffic. Up to 80 in Texas . Average economy for the trip was 50.5 mpg actual. I love my prius. Side note: my wife is somehow unable to keep the mileage up so I drove about 5000 miles.