I would suggest that you let the "smart battery" get some legs under it, like a number of years... The technology, or lack there of, is kind of scary in those batteries and could really get expensive. It will be interesting to see how they hold up. A buddy who builds lithium packs had one open last year and was pretty horrified at the execution of them.....

I am in the process of building my own bank and the technology is amazing but also a little complex to implement well on a boat.