I play both the Neo or Zelos depending on how the 66 year old body is feeling. I have the Neo in a set of P790’s. It is a perfect shaft for the lower flight and spin of that head design. Right now, I have the Zelos in a set of Mizuno HMB’s. I really like them for when I’m feeling a little off
or tired. The HMB’s give me a nice flight and the Zelo is a good match for a slower swing speed day. What I like best about the Zelos is it has no negative impact on the reproducibility of distance and dispersion. The HMB head is more consistent than the P790 and the Zelos takes nothing away from that.
Both are great shafts and other than weight, very close to each other in feel and performance.