I live in the rust belt and never had a problem removing or reusing the part. Even the threads at the end if the bolt never caused any issues.

I'm pretty sure that like most bolts BMW official stance is replace.

With 20,000# clamping force and 50,000# shear force per bolt they are in in for the long haul.

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2011 E70 • N55 (me)
2012 E70 • N63 (wife)