So I took your suggestion of conducting some MAJOR research on this devious company you speak of. There's 15000 total units in the wild, there are 575 pages on this forum since the first one landed in our community here. Let's say there's a malfunction post on every page(which makes up for users claiming multiple warranties, such as your case), will round that figure up to a nice 750. So with 750 warranty claims you'd be looking at a 5% failure rate.
Here's a little blurb I found in regards to electronic products average failure rates.
https://www.squaretrade.com/htm/pop/lm_failureRates.html
5%-10%(we'll add a couple points to account for all warranties we are not privied to). In my opinion this is completely acceptable and understandable. Especially, being that I knew this was a start up company forming from an indiegogo campaign(which I'm hoping everyone knows). This company is still a baby and was started/is being run by two young dudes who are trying to provide users with the best possible vape at the best possible price(highly underpriced when compared to competitors) made in the good ol USA! ..koodos to them for taking on such a daunting task and making it this far. It could've all came crumbling down during the indiegogo campaign like a majority of them do. This is not a mega corp with unlimited funding trying to push chinese manufactured/designed products.. not to mention they offer LIFETIME warranty.
The nature of use of vapes is "sticky" and electronics no like sticky. So ya, they had a few hiccups in design but seem to be ironing them out fantastically. Mine both work flawlessly since day one, with extremely heavy use.
Again I understand your frustration having to deal with so many warranties but they all came through didn't they?
Also, after a certain point (10 claims) one must start to wonder where the problem lies. User error perhaps? Not saying this is the case but have you been experimenting with your usage? Same power source for charging(wall adapter, computer outlet)? Maybe you have an angry post man who kicks your hopper parts to your door every time like "Ace Ventura". There's a million possibilities as to where the problem could be originating from.
I wish it all works out for you in the end and hopefully you'll be satisfied.
Not sure if everyone saying that "having to pay for return parts should be on Hopper's bill" is a newb to vaping or what but no company that I can think of offers this. Otherwise they'd become a cleaning service for us lazy folk.