Long lasting, havent encountered a defect
I have gone through maybe 25 of these.. not one defect found yet. The closest to defect was one that had a bit more resistance when pulling, but it wasnt a dealbreaker by any means.
When it seems its low on juice, standing it upright for a few minutes gives it more life.
I am a chain vape kind of person amd the battery lasts 24 hrs easily.