No wonder the OP is confused! People try to help, but mis information still remains mis information!!!
510's are most certainly available as a two piece: pre-filled cartomizer + 510 battery, available from a lot of vendors. (Sherid, you are an ultra member? )
100 mAh Ego? (Rob-o)
The problem with all this is that I have seen people start out with e cigs and rush back in frustration to the store to buy analogs and barely taking the time stopping to dump their e cigs in the trash. The Internet is confusing enough as it is when looking up e cigs since the lies that abound are legend with tons of misdirection and falsehoods. I just passed the one year mark analog free after +3 decades of 1.5 pack/day Red; if anything, I want to see other people succeed.
Only a dimwit would take up ecigs as a hobby; we are here to quit smoking so there is some sense of urgency to all this. In fact, the decisions we take here can be truly life saving.
I do not care if people call me a tyrant but if you are going to open your mouth to venture an opinion, at least get your facts straight. Ecigs are complicated enough without asking new users to put up with your incompetence and stupidity.
If I sound upset, I am. I just had a ex girlfriend diagnosed with lung cancer. She tried quitting with e cigs 3 months before I did, and gave up in disgust. We never got that close, but it was still someone I knew. Her failure certainly preyed on my mind when my daughter put a gun to my head and asked me to quit smoking as her MBA gift. I was thinking that my only hope was to lock myself up in a clinic to break a lifelong habit.
I certainly have made my fair share of expensive mistakes, but I kept at it. It has succeeded for me.
So if you are going to open your mouth, gets your facts straight. We are not here to proliferate ourselves, but to share information and learn.