Does increase fogging on lenses and sweat drips, however does effectively prevents ingress around the edges of the lenses. I have worn these playing ball sports and does a good job of transferring impact forces to the foreheadbrow and cheek bones instead of my nose bridge, which is nice if you get hit in the face a lot.
The foam does damage easily, especially if crammed into a carry case with other lenses. Hot conditions may also soften the adhesive used on the foam and may cause it to separate or "slide" from its original position.