I use the 58% packs. I don't like to use them until after drying to the point smaller stems snap.
You need O2 during cure, so even if in jars with these packets, better crack them open like normal or use a better method than jars. Construct a humidor with a larger one of these things, lol.
I put 8g packs into 32 oz jars. Even when fully dry i don't let them sit unopened for too long. Anaerobic bacteria is no good for bud.
You can recharge these packs. Not sure how best to sanitize them for multiple uses, though. They are safe to touch the bud, but probably better to keep separate somehow, like how they are used in humidors.