I usually round up the system. For distances in feet, they rarely appear below 5, so I round it to 1,5 meters. As for the pounds, I round it at 1/2 kg, and a gallon is roughly 4 liters. Round it up to the nearest easy number. I do not agree with the system of measurement used, but as the game was created in the only country other than Liberia that doesn't use the metric system... I understand it. In Fralia, our Argentinian shared world, we are currently developing a system that deals with metagame measures (5 ft = 1,5 m = 1 square => 1 "jump"), roughly translated to the metric system to deal easily with.