Which Progressive Dynamics Converter/Charger To Buy

I have 4 Lifeline 6v golf cart batteries wired in series/parallel. I boondock on occasion (couple of times each summer). I have a generator that I use if my 200w suitcase solar isn't a viable option (cloudy or sun is low in the sky). My wires are the standard 6 gauge wire that most RV's have. The wires connecting the batteries themselves are 2 gauge that I put together but beyond that, back to the converter they are what the manufacturer installed.