Swim Cap Club
As I aquasize 3-4 times per week, I love these as it keeps my hair from being exposed to chlorine.  I do not go underwater so I am not sure how dry they would keep my hair if totally submerged.  However, for my purpose it's more than satisfactory and many others are joining what we now refer to as the "Swim Cap Club" or the SCC.
Rating: 5 stars