If you have tried the herkles tank on a box mod then you will know how this once is but smaller and tough. The newer Kangertech Subtank mini came with my kbox mini 50w and I have been using it at 30-40w since I got it, the coil lasted me about 5 days on heavy vaping and the tank is holding up well for the abuse that I am able to put it though. If you want the tank alone its going to set you back about $50 but well worth it if you have a smaller box mod you want to put a tank on.
I have never had anything but bad luck with Kanger tanks. Every one that I've owned has leaked heavily. Not only that, but the Arctic, Triton, Atlantis 2, and Zephyrus tanks are superior in quality, coil longevity, and price.