My neighbor and I harvested together this year. I could keep up and sometimes pass him in his 7720 in corn, but I'd have to unload sooner. We both decided that we were equal in corn aside from the bin size on my 1640. In beans, he had a 18' and me a 15', he could cut about 55% and me 45% on any given day. When the beans got really dry though, I could run 4 mph and he could only run about 3.5 mph. Of course the smaller 1640 bin size affected me again. When in green stem beans-we were both slowed, but the percentages where still about the same.