WE are in the custom business and run two 9750's. We do not run any filler bars especially if you have good wheat. The main secret to the STS is to try to run fast enough to keep it full. Think you will fall in love with the machine, we think they are great except for a couple of things. The quality control at Deere is not what it used to be. Also parts seem to wear a lot faster than they used to(and cost lots more to replace). Wobble boxes do not hold up well when trying to force 60 bu. wheat through at speeds up to and including 6 mph, have replaced three this season. Good luck.