Amazon calculates a product’s star ratings using a machine learned model instead of a raw data average. The machine learned model takes into account factors including: the age of a review, helpfulness votes by customers and whether the reviews are from verified purchases.
This mask is so soft, I have had no issue sleeping with it on. The adjustable strap is great, it doesn't get caught in my hair and I can make it just loose enough so there is no pressure around the head and I can't even feel that I am wearing it. The size gives it great coverage and being black it is great at blocking light out. Sure if it is daytime and your eyes are open under the mask you will see a bit of light around the nose area but when my eyes are closed that bit of light doesn't come through.