Many of us have upgraded the cheaper WFCO converter to a Progressive Dynamics converter for better performance. PD makes easy to install upgrades. There are several threads on this WFCO converter topic in the forum.
My 2010 TT WFCO converter would never change its output voltage - always at 13.6 even when the batteries were fully charged - not good for the batteries.
A better converter will vary the voltage depending on the need - 14.4 for quick charging a depleted battery, 13.6 for normal demand, 13.2 for trickle charging a fully charged battery.