Lots of confusing info being passed around here.
I can confirm for a FACT, that the PowerMax units will all do "boost" at around 14.5v according to their particular charging profiles. The PPCs have a different charging profile from the deck-mount LKs in the "stages" automatic mode, but will still do "boost" at 14.5v as required, despite that 13.8v confusing info.
All have the adjustable voltage mode as well, so you can charge your batteries whatever their specs call for if the automatic "stages" mode is not suitable for your set-up.
I have no clue what Randy is doing with his "Boondocker" units, but they should be at least as good as the PowerMax units AFAIK.