I was fitted by Titleist rep and bought 918 ap1 with AMT r300 steel shafts. After playing for 2 weeks I did not like the weight and feel after playing Titleist graphite for 20 years. I am selling the steel shafts to buy graphite 918 ap1 graphite. My 912 ap1 had the tour AD 65 gram shafts. I looked up the shafts for 918 and saw several options. Could you explain the difference in Tensei, tour ad, and Kuro Kage. 60-65 gram shafts?