The first time we used one was in the UK - a borrowed one. We were traveling on an A road up through the midlands to Yorkshire. The road we were on had a lot of recent construction, they were removing quite a few of the roundabouts and making 4 way stops.
The first time we hit a "former" roundabout the GPS thought it was still there. It was a hoot watching our car "spin out" off road on the GPS screen and the woman rapidly repeating "recalculating".