My last pair were chromed but due to the location and the fact they are hard to clean where they are, they rusted quite badly. This time I decided to avoid that and fit stainless instead. The whole of the swinging arm was chrome, the arm, the brake rod, the torque arm, the brake plate, the sprocket cover, chain guard, all the nuts and bolts were either chromed or stainless. It looked awesome but unfortunately riding the bike through the winter wasn't such a good idea.
I still fancy a chrome swinging arm, my spare will be powder coated and the other I may have chromed again.