I was willing to pay to Otto to service mine because they are nearly 7 years old. They do not work on them and would not give me any suggestions of who might work on them. It did make me decide that my next set will have replaceable batteries. I don't know if any of the other manufacturers...
I bought a set of Otto's in 2018. About 2 years ago they would only hold charge for 6 hours, and now they will only hold charge for about 2 hours. The built in battery is not serviceable. I have really liked them but my next set will have replaceable batteries.
One of my buddies recently installed the L3i barrel on CZ457. He has the Manners stock and had open up the barrel channel a bit to accommodate the new barrel.
I received a stock back from Joe with the cheek piece installed today. He does really nice work, but has been a bit behind schedule due to health issues.
I use a ziplock baggie. 50 rounds doesn't take up much space and I keep it in my cargo pant pocket. When the baggie gets yucky from the bullet lube throw it away and get another.