Boltropes on the best setups still don't let the sail flake down and furl on the boom without falling out of the slot and extra handling to contain the sail. Usually a boltrope has to be pulled down even in dead calm winds. A good slug setup will let the sail fall down on itself when the halyard is let go...requiring minimal crew power to get the sail down. While you are working with a boltrope to get the sail down I will have a slugged sail already down and furled on the boom. Safety wise slugs rarely get snagged or break...in my experience owning several boats with boltropes, they are more critical to jamming than slugs. One of the first things I do on boats with boltropes is change to slugs. Can you tell, I REALLY don't like boltropes? Peace.