You replace the tank if it is cheapo plastic and your juice eats it. Or when you break it. I guess you could end up having one a very long time if neither of those things happen. Some of the pyrex ones will last until you break it... don't drop it and no worries. The atty is the part that is the disposable.
I think the flavor is better in a tank without the filler stuff that has to absorb the juice you instead have a wick. Personal taste though. Some people use the carts and never get a tank. I like the tanks, dripping into the carts over and over is more tedious than I am after. I can fill my tank like the cartos and have a lot more juice to vape, don't have to worry about filling it up on the go so much. Plus no filler taking up space, again more juice less filling. I have been lucky with the leak thing, haven't had one do it yet. Not to say I won't get one that will, just saying haven't yet.
