What's the different between a painted roundabout (left) and a Shared Space roundel (right)? If you're a realist, the only day-to-day difference is the latter are more artistic, but the former are much easier for road users to see, being high contrast against the blacktop. To this we can add that Shared Space roundels are vastly more expensive to build and maintain. However, in both cases there is a smoothing of traffic flow, and drivers and cyclists will mostly go around the circle (though a few incompetent individuals will drive straight across, risking a collision). But peddlers of the Shared Space concept will tell you that roundels (and they insist they are distinct from roundabouts) magically turn drivers into courteous, caring human beings. Alas it's just snake oil to sell their idea, and unfortunately people unquestioningly assume they are genii with a whole new paradigm in road safety. In The Netherlands, where road safety is a matter of civil engineering, they have conventional, salient roundabouts (not roundels) that have superb safety records, because they were engineered to be safe. And the central island is a good place for artwork or greenery, to make the junction more attractive.
