On the 'Vari, I'm just using Boge cartos. The photo is a ByLeo Cage tank.
I have one Sophia, but it was a little "fiddley" for me - I'll build it again soon, but with a carto, it's good or bad, and when it's good, I'm happy with it, LOL. The Sophia, I kept thinking I had to adjust it to get the flow right...
I've also got 2 Russians I use sporadically, too. Same thing for me - they'll work great for a while, but then I find I want to fiddle to get better wicking, etc.
I like your style Train. This is basically the setup I take with me every work day. The only difference is I use a afc Cyclone and a Kayfun. Which atty is that on the Provari?