I have three 55gal drums, and 2 are pretty thick steel. One is an AeroShell drum; 50 or 60WT for radial engines, one is a inner lined/coated drum that had non conductive hyd oil for power company boom trucks, and the last is a damaged drum of Delo 15w40 that got punctured in the top by a forklift and spilled ~5gal on the ground, that me and a friend hauled to the barn in order to save some friends from having to call in a hazardous waste cleanup team $$$; got 2 straps and a hand pump along with it. One is used for waste oil, the other is for diesel fuel but only 30-35gal at a time so I can roll it off the truck with the 4-wheeler ramps into the grass and then into the barn, and the other is still mostly full of 5 year old , high zinc 15w40. I would rather use steel drums versus the poly drums, as said already, for less fuel in case of a fire. With the the fuel in a steel drum, there can not be enough oxygen for it to burn rapidly, just slowly evaporate off, burning some of the fumes in the process. Only on TV does everything explode with enough force to level entire communities. As for condensation, use a 10-15 micron filter with a water separator, as long as the water is not emulsified in the fuel, it will drop right out.