It's an old thread, but I wanted to add my 2cents on why propane is better in my situation. I have used gasoline generators for over 40 years down here near the Gulf Coast. When I was younger, I had carb issues all the time, but eventually learned to end that by just running them once a month or so and replace my supply fuel every year and treat it.
Hurricane Katrina flooded our Gulf coast refineries and shut down rigs in the gulf, and there was no gasoline for several days, and even then, you would stand in line for 4 hours and they would only let you have 5 gallons. Wife and I had to eventually bug-out after I used my 40 gal. fuel supply and then emptied my 85 gallon boat tank.
We have no natural gas here, even though they have pumped trillions of cubic feet of it from under us. Propane supply is very dependable and our company assures us of uninterrupted propane supply. Those of us who have generators are on a computer printout that pops out to the drivers as soon as any tropical system gets close or is aiming at us. They top everyone off. Then after the storm, as soon as the road is clear, they will be making daily runs to keep everyone full.
I installed a 16kw professionally converted to propane and had my propane company bring me a 250 gallon tank. Once that was piped into my shop, I sent my little 3kw carb off to be modified for tri-fuel, emptied and cleaned the gasoline features, and piped the little generator into propane also. Then I got a wild hair and converted my older Coleman (Briggs) 10kw to tri-fuel. I also cleared that gasoline system. Hopefully I will never have to put gasoline in them again.
So with me, it is mainly about the unlimited supply of fuel. It is also normally cheaper than gasoline down here, and a huge plus is not having to store, treat, rotate, and handle gasoline again. I will probably lay in 20 gallons if a storm approaches, but after the storm, it will go into the Suburban because it loves the stuff.
My two big gens like fuel, so if running gasoline, it is a near every-other day concern with having to fill up 6 gallon gas cans. With propane, if the lights are out, the guy will come to me and when he leaves, I will have 200 gallons of fuel safely stored and connected to the generators.
After Hurricane Fredric, the bridge coming to the island was knocked down. Only way on and off the island was boat/ferry, or small aircraft. They built a new higher bridge and say it will be there forever.
While the new 3 mile long bridge was being built, our propane company barged over a large tractor trailer type propane tank, along with a delivery truck which stayed on the island. When the transport tank got low, they brought in another one on another barge, and just swapped them out.