The pro ring I believe is for provari. That seems to be what I remember in a vid.
Right. And it says the same on the vendors' pages as well. So I bought a ProRing along with my 22mm SnP, because I intended to use both on my ProVari.
So I get my package today from domo (super fast shipping by the way), I first swap out the top cap inner o-rings for the red ones that come with the SnP (thanks, technonut!), get the Sophia in the tank and set her up on the ProVari WITHOUT the ProRing just to see if it all connects nicely. Which it does.
I take the Tank/Sophia off, put on the ProRing, go to reconnect the tank/Sophia....and it's no bueno.

I can't thread the Sophia to the ProVari, it just keeps spinning.
It looks to me like the ProRing raises the tank far enough off the top of the ProVari that in order to make the connection between the Sophia and the ProVari I had to raise the tank up higher on the Sophia. OK, fine, now there's enough of the Sophia to reach down through the ProRing and make the connection with the ProVari. I slide the SnP tank back down so it is now sitting on top of the ProRing...
And the juice control segment (where the two pieces connect) of the Sophia is now nestled smack dab in the middle of the tank's bottom cap, completely blocked.
If anyone has successfully used the ProRing with a Sophia and a ProVari, please let me know how you did it. I am completely ready to have egg on my face for missing something entirely obvious. I would rather be embarrassed as a noob than realize that I just purchased a $25 beauty ring that I can't use.
I would use the tapered ring for a Kayfun on a 22mm tank.
Kayfun V3.1 ProVari ring - Kayfun 3.1 I have the 23mm SnP. One couldn't pry it out of my cold, dead hand. Best carto tank I ever had.

Looks Perfect on the 23mm ProVari. It's especially nice with the optional ProVari base for a clean, seamless look.
I don't have a Kayfun ring. I'm using my Loki Labs ring at the moment. and let me tell you, that s*#& is tight. And I don't mean that in a good way. It almost completely cuts off the airflow.