What Size (US vs. EU Sizes)?

Hi guys, I am from germany and looking to order some popflex clothes. I am unsure about the size, as US sizes often times run larger than EU sizes. Can someone from europe tell me if that is the case with popflex? should I size down from my usual size? For example I want to get the cloud hoodie and I want it to be a little oversized. I usually wear a german Size L/40. Should I go for the M/L Size or would that be way to big?