If you’re referring to the list on line that is sorted by the MPF, the MPF is sorted partly by stiffness in that the MPF ratings that start with “1” are more flexible than those that start with 2, 3, 4. However, within each code, they are not necessarily listed by profile stiffness. In looking at the detail of the two shafts you listed in our database, the Rapport 70 R and the Kuro Kage Black 2nd Gen 70 R have very similar flex profiles. Even though the Rapport is listed as mid/high trajectory shaft and the Kuro Kage is listed as a mid trajectory shaft, they are very similar and should produce similar results. I think either would be a good choice with the KE4 MAX irons. Just built a set of the MAX irons with the Rapport shafts for one of my old buddies (played high school golf together) and he loves them, for what that’s worth.