Here we are, my wife and I, on vacation at Wallowa Lake in north eastern Oregon, elevation 4,400 feet. We left at sea level traveled route 84 at 60-75 mph, speed limit about 50 miles or so east of Portland is 70 MPH. The Volt was loaded with all our gear etc. easily well over 4,000 lb's gross weight.
Arrived yesterday and went down to Imnaha and did some fishing and my wife took some nice videos.
Quite pleased with our 2016 Volt Premier cruising at 70+ mph and handled so much better than our 2010 Prius we used for the same trip about 3 years ago.
Right now at our cabin the dash screen reads 509.2 miles traveled just on gas with 10.73 gal's used for 47.5 mpg. Electric used is 32.7 miles with 8.1 KWH used, and 29 miles remaining. I don't believe our 2010 Prius could do much better or even match the Volt's figures.
Plan on going down to the Snake River Canyon, quite a ride in this vast wilderness area...