I forgot to say, in regard to keeping batteries in good shape, a tender will be far more energy efficient than the converter will be. I'd love to have a 30A outlet near my camper, that way I could run an extension cord through an adapter for a tender and then be able to plug the rig in to run the AC when cleaning or prepping.
Now-2014 Sierra 346RETS 5er BUB
Then-2002 Keystone Springdale 286RLDS TT
Nights camped in 2014-28, 2015-127, 2016-10