I"ve had the Istick50 for a little over a month now, with no problems. Once in a while it'll change from watts to volts or vice versa but that is no big deal at all, doesn't affect the vape in any way. I think it's a small minority of units that have had problems, as others have said. I'm not trying to minimize the problems but I don't think they are very widespread. I'd have little hesitation to buy another if the need arose. I do plan to start being more careful about charging it and such, as I tend to just plug it in and leave it overnight. Maybe not a good idea, I guess.