Locally, for me, the best and cheapest quality rn4081 is sold under the brand name nicotek metro. They only sell auto bats though. So, a few questions. I have two auto bats, and they both operate differently. One needs a really hard drag to get it to fire up the carto, and the other one is real smooth, you barely need to draw on it. Would manual bats ordered offline give me a more streamlined operation? Also, it's well known the bats don't last long charge wise either way you go. So my second question is, how reliable are the usb passthroughs for this model? I figure if I got one and used it while home, I'd have fresh bats for when I'm out and about. Third question, where is the cheapest online store to buy blank cartos? I can run to the store and buy the three pack they sell, but they are prefilled and I hate the menthol flavor. Not to mention 10 dollars for 3 cartos is kind of expensive. Thanks all.