Go into the RDA forum and look up the Hobo thread, lots of good info. It really is a mid sub ohm atty, not good at all below .4 as it gets very hot, and the space is very limited. I would`nt suggest 22, its more of a 28 or 26 atty. Its insulator is right at the coils and too much heat and you`ll melt it for sure, mine is deformed a little bit from trying to do a .2 twisted on it that I scraped for that reason.
Lastly, its not the most cleanly atty, it does leak a fair amount due to its design, so sitting on top of a regulated box may not be perfect combo.