I used these brand batteries Mawell, which expire in December 2018 (so far I was from the expiration date). I used them in 2 devices: - Heart rate strap (not really consume a lot: the original battery lasted at least 20 hours): life = 4 hours - A remote control (which consumes very little: the original battery lasted 1 month): TTL = 2 weeks
So of cheap batteries but does not really worth an original battery (count 25% of the lifetime of an original battery)