Got my rebreather when I was 41. I'm mainly a GUE diver, so I was doing a lot of OC tech and cave dives. A lot meaning obviously depends where you live and what you can do (regarding family, work, vicinity of diving spots, charters, etc). In my definition a lot was +30 trimix dives a year.
I dived for 2 years OC T2 and T2+ dives and got to a point where I (mainly mixed team since my buddies were all already on RB80 or JJ) it was becoming limiting.
I was still not convinced to switch over, because the only real reason would be enough JJ divers in my tech network to dive with, and then suddenly one of my main buddies told me he was going to sell his RB80 and get a JJ and asked if I wanted to join, then 3 other good friends joined in as well and suddenly we had a small group ;-)
So I bought it, started diving it in 2017 and then I got a divorce a new relation and a son, my best buddy (the RB80) guy got in a relation and got a daughter, another of the group divorced and basically stopped diving and another switched sports from tech diving to bicycle racing. So looking back our group was jinxed in some way ;-)
I moved to Italy, and kept diving (OC and CCR), although although the 100+ dives a year times were past with a son. It's only now 4 years later that it's getting more or less back on track and me and my original buddy (the RB80 guy) have decided to join another GUE expedition next year. Live I guess ;-)