When it comes to silver plating why would Hinkley be using a plating different from Sutton, when there are Govt. imposed standards? I have new Sutton's purchased a week ago, I will see how they hold up.
Also for some of the old ones I purchased some Rust-oleum metallic finish, "rich shiny finish fast drying", and I am going to try spraying several spoons, with three coats and see how it works on the upper water column. For the deep water 60-150 I use Stingers silver on one side, green on the other--usually works. Not all Stingers are silver plated, watch the packaging. I also use glow in the dark tape on one side, for deep water. I only fish Seneca Lake. You can tell if a spoon is silver plated by putting small dot of clorox on it, and it immediately tarnishes. You can remove the tarnish with a silver polish.