Now I will agree about the need for the 9750_9760 really needing more bin capacity. I watched at least 5,000 bushels of corn shelled in just 1 hour by a 9750, 12-row head, 235 bpa irr. corn, 5.5 MPH. I rode the combine myself. Now there were 2 big 1040 Kinze wagons running back and forth as fast as they could. It just seemed that for the combine, the ingoing stream of corn almost matched its unloading. About 80 percent of the time, the machine was unloading on the go. It seemed to only take maybe 4-5 minutes to fill the combine's 300-bu bin. It sure would not not be efficient to let that combine travel more than maybe 100 feet or so without the wagon by his side! What I'd really think to be efficient, would have that new Balzer wagons which can unload real fast. Just saving on unoading time counts for a lot in heavy corn! On second thought, scratch the idea of a 600-bu combine. The weight would kill those finals! A 400 bushel bin would help, though. I still would get away from such a skimpy corn head, though. Only 6 rowsIJ Come on! If only 6 rows, a 300-bu bin is more than enough. The 7700 even did 8. One thing the rotary combines do have going for them, though, is the fact they are not as sensitive to being underfed as are the walker machines.