I was looking into getting 2 x duel fuel 2500 watt generators. I couldn't warrant the cost (even if I had NG supply). I hadn't lost power for more than an hour since keeping reefs for 14 years. They are lightweight, portable, and propane doesn't go bad if you stocked up on a bunch of bottles.
Yeah. Found this... "Extended Service Intervals — Propane does not gum up over time like gasoline, because it is a gaseous and not a liquid fuel, so carburetor problems are not an issue. Propane combustion does not produce excess carbon and gunk like gasoline, and so propane engines typically have a longer interval between oil changes."