Over the past 3 years, we've never had any problems with this car. Haven't had any repairs done, just the regular maintenance. When I drive the car, it consistently gets 45-52 mpg (depending on whether its highway or city; summer or winter and whether the bike rack is on the roof); my husband gets a little lower--probably 42-51. Driving styles will definitely impact the mileage. As a short person, I love that I can see out of the car and the blind spots are minimal. Only having to get gas once every 4-6 weeks is a major plus; and we've driven the car from Chicago to Syracuse, NY on more than one occasion (a 12 hour drive), using just one tank of gas.
Fantastic gas mileage. Ability to see out of the car / lack of blind spots. Ease with which we can install car seats and get my daughter in and out of the car. It looks like a "normal" car. I like being able to watch when the battery is assisting the gas as well as the instantaneous gas mileage.
A folding rear seat would be great--but with the location of the battery, I don't know if that's possible. Daytime running lights would also be a plus (we just turn on the headlights, though). Back seats, in particular, are a bit stiff (doesn't seem to be a lot of padding).