I'm just about to order my second tank ever, and I'm interested in trying boge, primarily to see if there's a difference in the way the draw feels. However, I've noticed that my smoktech cartos have a little ridge on the bottom that keep the tank from getting pushed too far down and off the cartomizer, and causing liquid to go all over. From pictures, it looks like boge cartos don't have these. So do you just kind of eyeball where in the tank the holes should be and hope that the tank doesn't slip down off the cartomizer, or am I missing something?