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Most people in north america have trouble with 1-lame traffic circles, because they're almost uniformly too small. Traffic engineers like to wedge them in as retrofits, when there's already a lot of stuff built up around an intersection, and it's not feasible to enlarge the intersection to make it work well.

Traffic signals with good sensors are more space efficient, and usually more time efficient when there's congestion, and more pedestrian friendly. Proper sensor design means no or little waiting during low traffic times too. Traffic circles can help with akward intersections though, where there's more than 4 entrances or exits, and some three way intersections work well too.