Interesting reading here. I just got a Renogy 100w portable and I am already thinking of a better controller in the pass-thru and monitoring system. I see this as a long term project with upgrade to 6v pairs, charge controller and monitor, 12v receptacle in BR closet which is directly over battery compartment and where my CPAP resides, eventually panels on the roofs, etc. I don't see ever having more than 2 panels on the roof (famous last words), so I'll get a charge controller that would handle those plus the portable with some to spare.