I was reading through the dinghy towing section the other night and there were a couple of people using them. One guy bought a Harbor Freight unit and said it lasted about four years.
With that said, I like to keep camping simple, or often you just don't want to go or deal with all the added work. Having to pull it out every night and make sure it's charged would be a pain to me. I would rather install a charge line. You don't need anything fancy.
Don & Mary
2014 Newmar Dutch Star - All Electric - 450 ISL
2016 GMC Canyon 4WD Crew Cab