I think you mean Terry at St. John Welding. We have been running a St. John Rotor for 2 years in a 2188. It is very good in Milo, especially when the stalks are green. It also works very well in green stem soybeans. If you cut wheat when the straw is damp, I don't think anything will compare to it. However, when the wheat is dry during the heat of the day, it is easy to over-thresh it. For best results, a person should slow the rotor down in the afternoon. I would recommend this rotor to the owner_operator that is willing to dial in the combine to fit the conditions. If you are using hired help or want to use one setting all the time, the Specialty rotor is more forgiving. When properly set, I think the St. John Rotor will do the best job between the Specialty and the Standard Rotor. I have not used the AFX.