2003 Toyota Prius 4dr Sedan (1.5L 4cyl gas/electric hybrid CVT)
After 4 years of driving I have found the 2003 Toyota Prius an excellent auto in every category except for comfort. The newer models are 5 inches longer which should improve the comfort. My average highway mileage is over 50 mpg regardless of speed. In town mileage is closer to 45 (Toyota claims you get better mileage in town but its not true). It has plenty of power to go up mountains and can keep up with the best of cars and trucks on the Interstate. I have had only one minor glitch during the 4 years of my ownership and that was a minor computer that was replaced free by Toyota. Maintenance has been comparable to a regular gasoline car, except for the $700 cost of the 60,000 maintenance.
Gas mileage. Ease of maintenance. Smooth transfer from gas to electric. Quality of workmanship.
Comfort. More use of electric motors for in town use to increase gas mileage.