I usually wear an FFP3 at CCC events when I'm in an enclosed space. The only issues I've had so far is when carrying heavy loads (we need Engel, btw!) I sometimes soak the mask in sweat so quickly that I need to replace it every hour.
But the mask itself, if worn properly, provides no discomfort whatsoever.
But the mask itself, if worn properly, provides no discomfort whatsoever.