@Eskie brings up a valid point. The Zeus Dual and even the Juggerknot mentioned above are both great RTA’s, along with many others. But keep in mind there is a steeper learning curve when dealing with rebuildables vs a drop in coil and subohm tank. It is certainly not difficult, and there is always the experience of the forums to assist - but be prepared for a little trial and error.
With an RTA you are challenged at finding the perfect wicking technique. Too much wick could lead too dry burns, and too little could lead to flooding. There is also the challenge in finding the correct coil(s) that suits your vaping style and preferences. Nothing against the exotic pre-built coils that can be found through retailers, but it is beneficial to have an understanding on how these coils will function. Many are very high in mass which leads to longer ramp up and cool down time. More power is required to alleviate the ramp up, but that could also lead to a burnt tasting vape, especially if the wicking is not optimized. If interested in rebuildables, you may want to start will rolling your own simple single gauge coils. You can use Steam Engine to model these virtually to familiarize yourself with the correlation of the dimensions of the coil (amount of wraps and inner diameter), resistance and mass. And again, you can always rely on the experience of the forums to assist.
