The smart mode converter/chargers have the DESULF MODE built-in to run around 15.5VDC for 15 minutes or so every 20 hours to burn off the possible crud deposits on the battery cells.
These deposits usually occur when you do alot of 50% to 90% charge states charging which will eventually shorten the life of your batteries.
I would install a smart mode converter/charger system and allow all of this to happen automatically.
The newer trailers manf has started to add the smart mode converter/charger around the 2012 models and up.
The smart mode converter/chargers really take care of your batteries automatically for long life...
just my thoughts
Roy Ken