I’m building a senior set for myself. Using a lighter true temper regular shaft. I just can’t decide which is the better performer. I lIke the look of the KE4 tour better than  the KE4s.  Feel is the most important for myself, because I  moving from about 3 sets of forged maltbys. I think the KE4 tour might have the edge. All comments if you’ve played both are welcome.