Interesting read. I have had the ProIsoCharge 130 2-4 unit installed for about 4 years and never had an issue with it. From reading this thread I guess I was a lucky one..
I just (this past weekend actually) replaced it with a Sterling Alternator-to-Battery charger to gain the multi-stage charging capability I was missing with the ProMariner unit. My alternators are the original 52-Amp Motorola alternators that came as original equipment on my Ford-Lehman 120 engines. I am charging two group 31 starting batteries (start bank) and six 6-volt golf-cart batteries (house bank).