First of all there is no way you'll get 35 MPG driving 75-80 from V6 Camry unless you draft behind a semi for the whole trip. Just past weekend I was driving about 250 miles at 70 -80 traffic permitting and I got about 40MPG average, then I got stuck in traffic and end up with 42MPG for the whole tank. In summer you should get 35-37 MPG at those speeds and about 2-4 miles less in cold weather, rain or against strong headwinds. There is a trick to drive hybrid more efficiently and it's very simple: never trail the throttle, either accelerate hard or take it easy on the gas to just maintain the speed. I think Camry has a sweet spot between 55 and 65 MPH where you can easily get 45MPG, something to remember when the gas goes to $4/Gal this summer.