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.
Review is for the foam replacement on the facial interface. It's better than the original but I'm not totally happy with it as the material tends to "stick" to my face and leaves a mark on my face after wearing. Next I'm going to try the AMVR kit to see if it's an improvement.