Most, not all guys who have these on drills say they will meter the beans out better even if beans change seed size. I have watched belt meters run on a test stand and I can tell you they don't singulate seed much better at all than the flutes. Building plastic sliders in place of the radiator drop tubes will help you about as much as anything. If you already have a population monitor for your corn planter, put about four counting sensors on the drill and use your monitor on it. You can get along pretty good not spending the 2500 bucks on belts. gs