I got my new Showerspass elite in the mail today and, since I've never owned a official piece of bike-specific rain gear before I'm wondering how it's actually supposed to fit. I ordered a large because I'm pretty well always a large in everything else I've ever owned. The jacket fits a bit snug, though the arms are the right length. I'm fairly slender so that's not an issue. I'm just concerned I might not be able to layer a lot of items comfortably underneath. So do you all usually go up a size? Or is it supposed to be snug?