This has not materialized, because the batteries provide quite acceptable performance and in everyday use I could now bite not distinguishable in terms of maturity compared to the 'branded goods' notice although these are mainly in the retail sector (some many times) more expensive.
However, many of the more expensive products are advertised with their long shelf life, which I can not judge due to lack of experience, but there are batteries with me usually less than 1 year around before they are empty.
Back to the product, which is highly recommended in my opinion each.