I'm in the market to buy a 11.5' Kuhn discbine this spring, and I'm debating which rolls to buy. I've had previous bad luck with rubber on rubber (a Gehl),and great luck with steel on steel (Macdon). Salesmen have been pushing to use rubber, but I'm stuck on Steel. We run a 50 cow dairy, with a lot of grass alfalfa mix. I'd love to see others thoughts.