i would say you only would need a new one if you notice it hindering you in your play, now for instance the newer controllers tend to shield drop better and more consistently than older controllers, It would definitely pertain to how comfortable and effective the controller is for you, and if you notice that things you used to be able to do easily or more consistently that you cant do now than id say you may need a new one, as stick boxes/ potentiometers can become worn out and less sensitive then they used to be. The new smash controllers are great and only 20 bucks once they become worn in, if you have issues with not liking the way the bumpers click in i would just take the board out of the new smash controller and put it in your current shell, because going from your 10yr old controller to the smash4 one you will easily notice the shoulders feel very different even after the 5 months if wear on my sm4sh controller my platinum triggers Still feel much smoother , anyways hope that helps!