a Li-Ion in a lead acid world.

Thanks for testing and posting that, Brian. Well worth the read.
There's been much speculation about Li-Ions. The max voltage / power
curve bit is always a problem.
It will be interesting to see how the Universal batteries age. So many
batteries that we knew and loved seem now a shadow of their former
selves quality wise.
Are Sonnenschein batteries the best way to go? Tom Knauff stocks a
couple of sizes, but not all. Many web searches come up with
substitute batteries of lower quality.
Jim