My parents live in West Bloomfield. The township recently installed a roundabout at their main intersection. Before the roundabout, it used to take 2-3 traffic light cycles to pass through that intersection during peak hours. Post roundabout, the traffic is completely gone. There are many roundabouts all over that area, some with lights, most without, and traffic seems to flow through them pretty well.

I was skeptical about roundabouts too. Having experienced this, I've definitely changed my tune.