I think the difference is not only the base materials, but the attachment method used. The tapes are getting thinner, less messier and more undetectable. as well as stronger. A lot of these tapes dont really work well with skin systems from my experience, they are hard to take off the skin and leave a mess. So i think as the tapes get better and stronger, the advantages of skin are getting less. for me the advantages of skin are that it is water proof if you are underwater, The hairs dont go through the underside, and some cream liquid glues are easier to clean off skin than lace.