This video is great, but doesn't answer the question: why is this better than a normal screw conveyor? The answer, as far as I can tell, Is that the rotating "scoops" at the inlet feed the conveyor continuously, while using the screw alone lacks a secondary feed mechanism. Or is there more to it? Someone mentioned that the surface area of the tube works for you with the conveying instead of against you in the standard screw conveyor, but is the surface friction of the screw less than that of the tube?,(reply>), It doesn't push nearly as much air, so when working with fine substances like gunpowder, rice, wheat, etc, it doesn't spray them everywhere when they exit out the top with a gust of air.