You mention translation errors, which brings to mind:
Something to at least look at, "Five Year Warranty" often seems to mean five year pro-rated against list price
, so you will be buying
the replacement at a price
pro-rated against LIST not discounted prices. And often no initial free replacement period. Of course, the exact terms will vary by the seller AND by the country you are in when you place the order, so a bit of research
up front could save a big surprise three years from now. Unless the batteries really do last forever.
Some of the vendors appear to have very little experience on the consumer market, and as a result their warranty terms may be in significant conflict with warranty statutes wherever you are. Which can be a good thing or a bad one.