The Kaiken Flash seems to be permanent equalizing.
That said sometimes I have the same feeling as you about Lithium. The maturity for the cruising yacht market doesn t seem that established leading to complex not fail safe systems probably impossible to fix in remote places.
For the moment we have a system that works with Gel batteries (9 years old) religiously maintained and strangely still working. I haven t excluded the possibility of replacing them by the same brand and model. I was also attracted by the Firefly carbon foam AGM. And spending the money saved on a high quality Solar installation that would be ready when Lithium will be at maturity for our specific needs. I know the industrial research on energy storage by Lithium batteries is very active now and the results will pass one day to our little niche market.
Robust, reliable and easy to fix systems have there attraction....