how long are controllers designed to last? Mine has hardly been used compared to my 360 pads and now it keep moving forward all the time! And moving backwards too if I pull the left stick down! Is it worth getting in touch with Microsoft? will they replace it? Or do I need to shell out for a new one? If so I am worried it will do it again! Do I go for an official one or find a third party one an hope it lasts longer?