I have the ZX5 MKII irons and have th TGI 60 in the 5 and 7 irons. I was actually fit for them during a Srixon Demo Day for the ZXi5/7 irons and wanted to try them after a bout with tennis elbow. I was surprised at how well the 60 orbs for me, turned 70 in July, I built them to D1. My main concern that they would be too light and loose control but hit a surprising 5 iron this weekend, 7 i on into a green as well. I ordered a Recoil Dart 65 to try before I commit to the TGI. 🏌🏻