Although I and my wife have not touched a cigarette since June 2013, we have, for the last few months, been very disappointed with the life of the cartridges, some of which last only a couple of hours. When we started using OK E-Cigs the cartridges would last the whole day, now we are using between 2 and 3 per day!! My sister also finds she has the same problem. So come on OK, get your quality control sorted or you could lose our custom.