Really unnecessary if you follow some really basic and simple rules when charging/using/storing Lipos.
What I find interesting, by the creator's own admission, they were NOT following the rules of charging Lipos safely is what caused them to create this product. They admit being "careless"....
As I've stated in another post, in the many, many years of using Lipos in R/C I've only seen one fire, not an explosion. Started with smoke and slowly developed into a flame. This happened because the battery was improperly charged...
I've stored batteries for 3 years, charged them and used them and they worked fine (won't say they worked exactly as they had 3 years earlier when I stored them. But there was no noticeable loss of power or capacity)