Condensation and sore chin
I agree that it is lightweight.  I wore mine for about 30 minutes to an hour outside in the Colorado cold.  I was moving present from car into house so really moving.  I have one homemade cloth mask with the folds or pleats in it.  The mask fits perfectly in this one.  I have another where the mask is a little bigger and it doesn’t fit as well against my face.  I would say a snug mask works perfectly.  It was just starting to hurt my chin area just below my lips.  The fit is weird to get used to.  When I took the mask off the soft plastic piece had condensation on the bottom half which left my skin wet.  Maybe that won’t happen if you aren’t moving and getting heart rate up and breathing hard.  I did have a light ring around mouth when I took it off.  Maybe my mask was a little too snug.
Rating: 3 stars