I have used the metal ones for years on various models of BMW's 335, 545, several X5's with no problem whatsoever. Except that somone stole one once. I have a set with the Roundel on it and I have a set with the M on it for my M. Maybe the difference is they don't use too much salt up here in Washington and that I typically check my tire pressure once a month so I screw and unscrew them frequently.

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2013 BMW X5 M