There is an issue with them though. If there is very unbalance traffic flow in one direction through the roundabout, traffic from the perpendicular direction te

There is an issue with them though. If there is very unbalance traffic flow in one direction through the roundabout, traffic from the perpendicular direction tends to be perpetually forced to yield. And only being allowed in the roundabout by some graceful soul. This can happen on routes where there are multiple chained roundabouts, that usually results in traffic coming at an even rate with no gaps in between.