The advertised claim is 1000 charges. can it live up to the claim? i tend to suspect that it is much lesser. of course, it can be charged 1000x or even infinite times physically but to be valid, each charge must be as long lasting or at least 85% of Day 1 capacity.
sometimes as the batteries and the camera age together, it becomes terrible. the old camera is extremely hungry for power and the aging battery is struggling to perform. in the end the battery last only 1/4 or less than when both equipment were new.