I have seen several near misses on the roundabout closest to the sparks road end of curletts.
South bound traffic can exit the motorway and turn right into the roundabout from both offramp lanes.
West bound traffic coming into the roundabout from curletts road can go straight thru in both lanes.
There are 2 lanes on the onramp to enter the motorway for south bound traffic. Which implys that both lanes in the roundabout can enter the onramps.
Many times I and others have witnessed the car on the inside of the roundabout move to the left to enter one of the on ramps, only to be cut off by traffic in the out side lane going straight thru.
Only a matter of time (if it hasn't happen already before there is an accident.