The state put in a roundabout in my town last year on an a relatively busy county road with a turn towards a new elementary school. While a lot of people had big opinions on it before it was built they figured it out pretty quickly, to the point that it's a non-issue. My manager, who is kind of a crank, noted the first day he used it to drop his kid off that he didn't expect it to work but it ended up being really smooth. In my experience drivers now are more consistent at navigating the roundabout correctly than at following right of way at any of the 4-way stops in town.