That says it all. We just installed some SF neon signs using Hilti HT-70 and threaded rod on cinder block walls. We wanted to use SS (I have a load of it left from a previous job), the engineer speced galvanized. He stated that SS will fail before the galvanized will. IDK myself, but if he signs off on, it I'll take his recommendations. YMMV.
Very nice signs! Great manufacture is what is lacking so much in our industry right now. So great to see something like yours! Can't wait to see the night photos - if the ones here are any indication they should be amazing!