I just got a subtank mini a few days ago and so far have been more pleased with the rba section than the OCC heads. The key for me has been to make sure the included coil has even spacing between the wraps and none are touching (this gave my first attempt hot spots/dry hits). Then, I found that wicking with a decently thick, not rolled or twisted, piece of Japanese cotton worked better than my usual minimum amount of cotton in my drippers. Also, if you get dry hits when at a reasonable wattage, try loosening the barrel section that screws onto the RBA deck slightly before you screw it into the tank. This seems to help with wicking my 80/20 juices. Good luck, keep at tinkering it gets fun after the frustrating first few builds.