ihman, For what it's worth, in soybeans we are running 2 30' 1020's with air reels here in NCIA (fairly flat) pushing them with an 83 1480 (no tracker) and a 04 2388 w_tracker. There is an advantage for the tracker but the 1480 doesn't do bad, you sometimes have to drive at an angle on some uneven places, it's amazing how much flex across the 30'. We have 24.5x32 set wide (132") same for the 2388 w_900x32 Trellborgs. Have never run duals so can't comment. The JD's in the area are running duals that are pushing 25and30 don't have contour master, though any new ones coming now have it. Any doubt, go with the 25', you'll be satisified plus will be able to move along at a goodly pace. My $.02 worth.