Have had the e-stick system for 3 months. No trouble with the unit and it is still working fine with the original battery. Order the refills direct from Vype to take advantages of their savings, delivery usually takes 2 working days from placing order on their standard delivery. Only had one cartridge failure which I guess could happen to any system, on the whole pretty good. As the cartridges are manufactured in the UK you can have piece of mind that controls are in place on quality of materials. The only downside which is more than a niggle is that the cartridges could last a bit longer, if you were a heavy smoker (20+) I would look to go with the e-pen