Inverter or if it's only a few hours, leave it off.
If you go the inverter route, make sure you either have a big enough battery or check that the truck can really send some power back to keep up...the standard battery charging connection is often pitiful.
Friends with a brand new rig, have to run the generator if they are dry camping after an 8hr travel day because it runs the battery down low enough that they can't make it thru the night. I tried to walk them thru how to address it but they were frustrated that it shouldn't work right out of the box.