Agree. It does have problems and I have eight of them that I rebuild all at once using premade FT coils. About a 1/3 of them don't work well after every build, don't know why and a couple of them fail after a few days use. I can't seem to get a stable vape going anymore. Perhaps they are just getting wore out. I'm thinking that perhaps I need to upgrade what I use. One or two better quality rba's might stop the constant atty swapping I have found myself doing for the last year or so.
Cappy, I still use some of the A7s too, but if you can get one, nuppins from pdib are my new favorite!! Mostly due to the better machining and heavier metal, but more expensive attys seem to work better.
I've been wondering if it is because of the higher quality of the rubber insulator for the middle positive pin on the more expensive units is the difference, since I can't figure out why they work better, the designs are so similar.