I still pull them off and give them a few whacks with the claw end of a hammer and bust the plastic off and expose the copper windings inside. The 2 yards I normally use both have rejected fans before, but neither one has ever given me any problems when I have the plastic busted off. I do the same thing with flyback transformers out of tvs and monitors. They won't buy them whole, but when busted open so they can see the copper inside they never question them.