The bright metal on the mouldings is stainless steel and not chrome so the issue of chrome going bad over time is not an issue. The differences I have found over the years involves the black rubber and fit. Aftermarket mouldings seem to have an inferior black rubber that begins to go bad fairly quickly and I have also found the fit not to be the best. If you sre building a show car I would recommend MBZ parts. If a daily driver, the aftermarket parts will work.