Metric system rules, the problem is that when you go to europe and jump with european skydivers, how do you agree on the brakeoff altitude and stuff... Everyone carries calculators ? (I started skydiving in US and somehow 14,000 feet seemed so much higher than 4k...) I like it simple, 0 is when everything freezes, 1km is a 1000 meters, and so on.. The English system still confuses the crap out of me, but I'm a born Polack though...