Good questions you pose, and I'm monitoring the thread for informative answers as well. Unfortunately I have no experience to report on the products you list.
I note there is a majority of opinions that advise against splitting a house bank in two, partly because it causes each bank to suffer a deeper depth of discharge than would be the case for a combined bank. Depth of discharge having a bearing on the longevity of lead acid batteries.
It does occur to me that if, for whatever reason, I HAD to have two house banks, my first approach would be:
a) Monitor the state-of-charge of each bank with a batt monitor (with DOD alarms).
b) Based on monitor readouts, I would manually switch drawing betw banks
c) Based on monitor readouts, I would manually switch charging betw banks
Essentially, I would do (b) and (c) above in a way that controls the depth of discharge of each bank, while at the same time ensuring each bank does a substantial share of duty.
I am sure it is feasible to build a smart charge/discharge controller that can do this automatically for two banks. Such products probably exist for the super-yacht market, but I doubt they exist for the cruising sailboat market/budget. Still, you never know.