I’ve had similar faults with both brands and always ended up fitting genuine. About a year or two ago when you got the Febi TVD pulleys they where genuine ones with the BMW logo ground off but lately that has changed (and so has the quality).
I doubt it’s anything else at fault other than the pulley itself.
Afaik the value line kit bmw do for it is about 350-400 which is great considering what your getting (no.2 in the link).
http://bmwfans.info/parts-catalog/E6...ly_value_line/
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