I'll have to replace my budget stock KMC Z410 when I install new cranks. Just wondering if there'd be any significant performance gain with a not-the-cheapest chain? The silver plated ones are advertised as generating less noise but I doubt any chain could be heard over my clickety-clackety sturmey archer hub. Looking at the higher end internal hub Dahons they appear to use the anti-rust version which is mildly more expensive.

Performance gain? No, but in my opinion if you upgrade to an anti-rust chain then you won't have to oil it anymore. There are, however, those who disagree.