I am the proud owner , of a new Glock G43 and the rails etc have a brownish crud on them that looks like rust. I know that the preventive grease that Glock uses on them now looks like rust. My question is should it all be removed and re-lubed with oil or something else? It doesn't look great on the rails snd zi was once told by my LGS that it was to prevent rust. But is it adequate lubrication or is it more like Cosmoline and should be removed?