They are putting them in in Michigan. I hate them, they are confusing and dangerous. The newest one near me is going on an expressway overpass. What a disaster that will be! Why not just put in traffic lights?
They are not dangerous. Fact is data shows they are safer then semaphore controlled intersections.
They are usually only dangerous for a couple months until drivers in the area figure out who has the right-of-way, and which lane they need to be in to get to their exit point. Give them a chance, and be extra vigilant until everyone figures it out.
They really do keep traffic moving. I’ve seen the effects of pre- and post-roundabouts. We used to sit at stop signs and traffic lights for 10-15 minutes during rush hour. Now there is very little backup and traffic keeps flowing.
Why not put in traffic lights? Well, the road builders can’t charge you 10X more for the intersection, and the road builders spend allot of cash to get what they want....