First the good things. The mask is very light, soft and no light is coming through. It fits my face well enough, and does not irritate my eyes. It certainly improved my sleep. Even sleeping on the side is ok, the mask only shifts a tiny bit and still blocks out the light.
But: The elastic band holding the mask in its place is far to narrow to be comfortable. And it is difficult to find the right "tightness". If too tight, the mask will cut into the ears and the mask will be pulled onto the eyes too much and light may enter. And if you loosen it just a tad too much, the mask starts slipping and moving on the face. I am also wondering how long the elastic band will last...
Finally, for what it is I find the mask a bit overpriced.