Any grip, as long as it becomes worn smooth to make sure you have a good club held, for safety, need to be replaced. For those who have a passion for the game, while advances in technology and design, the advantages and disadvantages of the materials needed for testing and design versions, and is expected to lead to improved and more enjoyable game.
Metal shaft is usually very stiff; some players believe that this allows them more control during the swing graphite shaft bending, which may in their likelihood of more accurate shots and some of the more skilled golfers’ better distance.
With advances in taylormade golf drivers technology to reduce costs, players try graphite shaft which is becoming increasingly popular. I think in the future we cannot see the metal version.