So, I have the 20S and it gets used and hour a day, 5-6 days a week. And my battery lasts about 3 weeks before I charge it. That pretty much matches what they advertise of 13hrs battery life. And my units are 7 years old. I also found that the 30K only lasts 8hrs in mesh mode. I ass-sume that mesh mode will eat a battery quicker. Solo riding might give more battery life. I charge mine when it quits on me or right before I think it's gonna quit on me. Lithium batteries don't like being "topped off" and it will shorten battery life over time.. . . . My units still work great, but their batteries are getting weaker. . . .
Regardless, new 30K batteries are only $30 on Amazon; cheaper elsewhere. If you like the system, a new battery is the way to go. I also found plenty of vids online to show how to replace the battery.
After hearing my kid's Cardo, and the poor customer service others are receiving, I'm sticking with SENA. My 2 cents.