Yes same here on both f56 cooper and roadster s.I find a good polish with autsol leaves a great shine and for a couple of months at least it sponges off. Worse on the roadster s i assume because it does fewer miles and shorter journeys as stated.above.
Much cheaper than I thought they would be, 50 bucks for the set. They remove with a set screw in the bottom. But to be clear, these are the chrome tips from the tuning kit not OEM. But unless the tips on the OEM are welded they will likely come off in a similar fashion.