In Comparison to the old brush and pole technique, There's none. I joke with my clients declaring I come to feel like I really should give refunds to everyone who I cleaned with a brush. The spinning method does a far better position. The spinning system also involves glazed creosote https://www.google.com/maps/d/edit?mid=1GjdBxd3c7dq_F5Fo8pNXpVc26rlFsVw&usp=sharing