So it seems like there's different versions of the Power Magic Pro as well. The cut-off voltage settings described in @
F1point4 guide are 11.1v, 11.4v, 22.2v, and 22.8v.
The Power Magic Pro I got has 11.8v, 12v, 22.8v, and 23.2v cut-off settings.
I'm going to try 11.8 and see how it goes.