To drive in Singapore, one must plan the route. Last minute stops and detours might trigger more beeps from the IU gadgets even more so now with new gantries being setup. Decision here is, would paying $3 into the CBD zone saves petrol and time than crawling along the outer rim. To plan the journey so as not to pass through the CBD too many times. Time is of the essence here. Another added stress to drivers. It would be a driver's nightmare to be caught lost in the maze of streets in downtown business district during office hours. Worst if the one behind the wheel is the cab driver!!!