I have been in combines alot because of wear and so far the 60's are looking real good with the high wear package with the exception of the transition area on the floor of the feederhouse pivot. There are several guy's that went from two 9600's to one 9750STS and it added only about 5% to their harvest time and repairs are a little less per bushel, the 60's will wear, I think, 60% better than the 50's. This is in 75 bushel ave. wheat in Mount St. Helens ash.