I've been using one for about a week and it works pretty well. The menu system is a bit wonky, but once you figure it out sort of makes sense. I've found that some Smoktech DCT cartos won't work; I think the threads on the device are located a bit deeper down the socket of the device. No problem with Boge cartos, though. Have used both flat top and nipple top batteries with no problem. I also have a Lambo, and the two are similar in size and function at about the same cost. Overall, I'm happy with it and will have to see how durable it proves to be.