I use a SRAM PC991 on my hybrid that does the bulk of winter miles, and this seems to be a decent improvement in predisposition to rust compared to the PC971/PC1031 I use on the recumbents (which really do need a wipe down when exposed to winter skog), and vastly better than the Shimano HG53 it came with originally and whatever Brompton use as a stock chain.
Disclaimer: It's more about not rusting solid if you come home soaked and then ignore it for a few days, rather than an absence of visible rust.