More comfortable if you position the seams to the side of you head so they don't dig into you forehead. Fits very snug. Stays on when you pull off your helmet. (Would rather it didn't though). Had a nylon one that blew away in the wind and preferred it.
They do the job. On hot days just soak it down and it will keep your head cool between fill-ups. Just buy 2 or 3 because they're small and don't take up any room.