Whatever you decide on, test it first. My MVPs hot pin seems to be too far down for most tanks to work. I don't think I found anything other than eGo threaded devices and the Protank that worked well on mine. But I would agree cartos are nice!! After trying clearos, RBAs, RDAs, and carto, I've settled in nicely with the Diver and a Phiniac tank. But because I want the carto, my MVP is now a backup to the Sigelei....