A two piece system is easier for the user I guess, bu what about the wasted material? those atomizers are being used a few times then tossed... Seems a waste. 3 Piece, less convenient, but less wasteful. Not a huge inconvenience to clean/replace after some time imo.
as for the ROK model of this e-cig... It is clear that some manufacturers of e-cigs lend their models out to branding, such as ROK, BIONIC, BLU.... Each are different in ways. google ROK e-cig and watch their video, looks exactly like BIONIC. Not saying this is bad in any way. I love the bionic. My friend came to visit who was a heavy smoker who has quit and couldn't put the damn thing down. He is NOT going to buy it for now because he knows he would be f'd and be smoking it all the time and he doesn't want to get into that. But it goes to show you that this product is awesome.
