How are the 8120 performing with 35' drapers? My 7120 is running 1000-1100 BPH. 3mph. When I unload on the go I have to back off to 2.5 mph. In soft ground it dies really quick. I'm running SW concaves and Skip-wire crates. Grain travel vanes in slow over concaves and mid setting over crates except very last vane is in fast setting.