Have a 36v MK Ulterra, with (3) Cabela’s Group 30 AGM batteries. For the last 3 years I’ve “almost” made the change to liOn’s; with cost being the main deal breaker, along with the need for a special charger, plus (depending on brand) specialized conditions for cold weather applications. A lot of my boat use is in the winter in Eastern Washington, and while my boat has a full cover, it lives outside. I don’t want to R&R batteries every time I use the boat, plus the original AGM’s keep performing after 6 years. Once they’re TU, I will move to liOn but I just couldn’t pull the trigger until then.