I guess I don't know what the question is ...? Things break, stop working, or don't work as well as we'd like/hope ...I'm not sure what you want us to tell you, we can't provide a guarantee that what you get will last for years and years.
If durability and longevity are truly a concern - if not THE concern - for you, get a Provari ...not because they are better built than any other mod (although they are), or because they are guaranteed not to break or stop working (they aren't), but because they come with a 1 year warranty and an option for an additional year. I don't think there are any other VV mods on the market that offers a warranty, but I could be wrong.
When you are dealing with man-made devices, you can't guarantee they will last forever ...the best you can do is plan for the event when they don't.