I know an owner or two, and while they never hit the originally-advertised ~65 mpg numbers, 50 mpg sounded easy to achieve (without holding up traffic).
First hand experience, I drove a rental for 3 days. Most of the time with 4 people and luggage. Mostly slow driving, some mountain roads, short spurts on a highway. I wasn't driving to save fuel (there was no fancy display telling me what was going on underneath) I was trying out the acceleration, seeing when the ICE kicked in, switching the regenerative braking on and off etc.
According to an online converter, from memory, I got better than 65mpg US. It was a Japanese model, on Japanese fuel, which may make a small difference.
Sorry, back to the original topic.