As mentioned I'm storing it but with the intent of cycling "old" gas out over time since it can be run in the dually. We've been through enough extended power outages here that my ass still hurts from kicking myself for not having bought a generator sooner; I don't need it also hurting from failing to have enough gas on hand that it becomes a scavenger hunt through a city full of flooded (or iced-over) streets for a station that is open and pumping. No idea how long 20 gallons is going to last but I think it's a reasonable amount to start with.
Richard
My generator, is a 7500 KW, with a 13 H P Honda engine on it. 7500 KW, is a little small, but good for emergency use. My house is 1800 SQR feet, central air and heat. So what I do, is close off the 3 bed rooms, and the wife and I, move into the living room. The generator, will power everything in my house, except for the AC unit, so I have a Simi large window unit, that we put in the living room window, and cool off half of the house. I have a welding machine in my small shop, that has a 50 AMP breaker, so I kill the main power breaker, in the house, to isolate the input from the city fed lines. Then I have a pig tail that I use to back feed the house, from my shop, where the welding machine plugs in. When the city power is restored, I kill the generator, unplug it, then last of all, put the main breaker, back on. This works grate, but you do have to be sure, to never back feed the power supply lines, to your house. By turning off the main breaker, this insures that you are not back feeding anything. If you back feed the power lines, it can kill anyone trying to repair the power lines, down the line, BC you generator, will back feed, your transformer, and this will step up the power, to the main supply line. By back feeding my house, with the mine breaker off, all of the plugs, and light switches work. The refrigerator works, as does anything else that normally has power. This is simply what I do, and ONLY recommend back feeding you house, ONLY if you have some experience wiring houses, and breaker panels.