I have a hornet, which is a slightly smaller ERA. It is very good quality and an awesome vape.
I was initially uninterested in RBAs and slightly intimidated by the process. Then I bought a hornet and gave it a try.
Making the coil is very easy, slipping it into the holes on the posts of the hornet (or ERA) is very easy and inserting a rolled cotton wick thru the coil is also very easy.
What is the most amazing is the quality of the vape. You will likely find the entire rebuilding concept quite fascinating and engrossing - fun, like a hobby. Not to mention that for the cost of a disposable atty or carto you get enough wire and rolled cotton to make dozens of coils and wicks. Once you have a decent coil installed, you simply change the wick when ever you want.
The hornet is not inexpensive, but IMO, money well spent. Roughly 6 months of disposable carto costs to buy a hornet, but I believe that it will not only last much longer than that, but you will have a better vape, the knowledge of exactly what materials are in the heater and the pride of knowing that you built it!
I say get one and get after it. Let me know if I can help in any way.
Shot thru cyberspace with my iGun