S&W switched to a more EPA friendly bluing process around year 2000. It produces more of a black finish, which might be just a bit blacker than the 1980-2000 black oxide bluing. Up to about mid-1980, the blueing had a very blue look to it, it was the old Carbonia oil blue. If your firearm was made after 1980, then the current refinish may be acceptable, but if yours had the Carbonia oil blue finish, you might not like the refinish. Also, the current black oxide is reported to be sensitive to ammonia, S&W advises against the use of solvents that contain ammonia with this newer finish.