What sort of vape do you prefer? Mouth to Lung? Direct to lung? Subohm or higher ohm? What device will you be mounting the tank on? It all makes some degree of difference.
I'm in no way an authority on RTAs though I have some that I used for a time then stashed them for emergency use if needed.
I am somewhat experienced with the old shaky fingers tho.
I do have 2 Subtank Mini, great tank, and have rebuilt The RBA head a few times. Certainly doable but far from enjoyable. Currently using my STMs with the throw away Coils that came with them, when those coils are used up the tanks will be stashed with the others.
Now to my point. I've found my preference In Joyetechs CLR coils and the dozen or so tanks that accept them. Yes, they are even smaller than the STM RBA but a joy to work with. They're rewickable and rebuildable by design. I don't find myself needing a 3rd hand!
If you like you can check the thread devoted these tanks and coils
here. Plenty of folks there eager to bring you up to speed on them. Just skim over the last few pages, introduce yourself and ask questions.
Edit: And many, maybe the majority, of us in that thread are "older persons"