But I have read about this on another Blue Sky MPPT post somewhere. I'd look at other products.

BTW I also have a Xantrex C-12 in my spares that I replaced with the MorningStar and see no difference in charging performance. The C-12 is much cheaper and just (almost?) as good, IMHO. If there's any difference it amounts to a hill of beans for a lot of $.

I'm using 8x20w panels in parallel with a diode on each output. I'd considered going series/parallel to double the voltage, which might show better efficiency from the MPPT but that would also mean any single panel in shadow from rig/sails would have twice the detrimental effect. Still on the fence with that.