Will Prowse was enthusiastic about the SOK lithium battery when we were switching to lithium. It's worked great except for the phone app feature that reports the state-of-charge (SOC for the SOK -- confused yet?). We added an inexpensive shunt to our electrical system and ignore the phone app SOC numbers, and the battery has worked flawlessly for 1.75 years. That's not a long time... it had a long warrantee from Current Connected though. SOK supposedly has fixed the SOC feature.