I have a 1300mh DAV and the Ego kit. I've noticed that I'm burning thru cartos too quick for my liking. I know what to look for in a carto (brown/dark spots visible after cleaning) that indicate that the carto is bunk. So, I don't know much about tanks, but would like to upgrade to tanks. Everything I've read says that tanks are superior, but I'm confused about dual coil vs. single coil, ohms and what type works best with which liquid...etc. Anybody have any thoughts?