I just bought some rebuildable cartomizers (like Sophia, Diver, etc). I picked it because it had no ceramic cup, and was straight so could fit into any type of carto tank after being rebuilt. But there are no directions for rebuilding, and I'm not even certain what they are. When I took it apart, I noticed that it seemed to have a resist/no-resist wire join. I was wondering what the advantages of resist/no resist in coil building vs regular kanthal coil was. Why are they used in certain builds and not others? It seems they are most often used in ceramic cup type atomizers, and that's the bigger criteria rather than size. Mine has no ceramic cup anyway, so why did they do this? Any help or guidance would be appreciated, this is confusing.