There are a ton of RDA's to choose from. It's a preference as always, but there are some things to think about that will help you narrow down your options. First off air flow. Do you want single coil and dual coil capability? If your not into drilling out your air holes then make sure the stock airflow is enough or not too much. Second would be number of post. Do you like the standard three post set up or are you a 5 or 6 post fan? Third would be chamber size. Do you like a smaller chamber for that really dense hit or do you prefer a bigger chamber to help with the heat? Does the RDA come with a Delrin insulator or not? I'm a big fan of the Stillare by Cartel mods. It's a three post set up with a pretty big chamber and nice big air holes. On the flip it's only capable of dual coil. The TOBH is also great. Hope this helps VAPE ON!