I'm kind of dubious about them. I thought 45 mpg didn't sound like all that much, but an owner explained that that is 45 total, including city driving and that sounded better. Living in a city that tried to evacuate itself a couple of years ago, and wound up with thousands of vehicles running out of gas on the side of the road, I have thought it would be real nice to have a car that didn't burn fuel when idling. OTOH, where I live flooding is also a prime consideration, and I kind of like my nice tall four-door pickup for going through high water.
30 years ago I had a little Honda 600 coupe that got 42 mpg. Of course it was even smaller than these hybrids...