We run two small inverters, one 150 watt for rear TV, one 500 watt for front TV, satellite box and DVD player. We can last one night with two six volt batteries during the winter with furnace running.
I would not try it with two 12 volters.
We run the genset(onboard) for a half an hour or so while doing breakfast. It does a fair job to charge batteries but they are not nearly fully chrged after shutting genset down. We then run genset in afternoon or evening for another half hour or so to put more charge into batteries.
I upgradedthe converter to allow a larger charge into the batteries from what came with the rig. This helped alot in battery recovery rate going from less then ten amps to 55 amp rating.