I put the 3" hose on a 300series 18foot head on my R52 this year. Clamped every 14". My beans are very short and yielding 10 to 14 bu and it is doing a great job of feeding. Not one feederhouse plug in 100 acres! Stones still get in but I think a little less than before the hose mod. I have the AHHC in the second setting from the lowest and that helps the stone problem. I'm travelling at 4.5 mph