Planted between 600-650 acres a year with an IH 56 4r38 for years. Combination of grain sorghum, cotton and soybeans. Pulled it with a JD 3010 in 5th gear (about 5.5-5.75 mph because that's as fast as it would go). I disked the ground with a Ford 9000 and a 20' IH 475 disk, my brother put out the pre-emerge with an IH 706 and a 12' W&A Do-all, and Dad ran the planter. We usually hired someone to tote seed. In cotton he would also usually band a pre-emerge right behind the press wheels on the planter. Usually had the dealer to broadcast the fertilizer with a spreader truck ahead of the disk. We thought we were really doing something. Dad would normally expect to cover about 50 acres a day on average. Our biggest fields were 20-25 acres. Most were in the 10-12 acre range.