My biggest thing is i'm on a well -- i need 240v, and that means a big portable system with a running consumption of a LOT of gas. Gas doesnt' store well. and when there's no power here, the gas stations don't have it either.
The truck bank as a back up would be a true back up... keep the fridge on and let us flush the toilets for a few days. If i'm not home, there's likely nothing in my fridge anyway, and who needs water?
