Stainless Steel Ain't
Some grades are more resistant than others - but - eventually left in the rain ALL will rust. Most often will start where the spokes cross each other and where nicks/scratches have occurred marring the smooth finish. It can actually result in a mid-section snap as opposed to the common head snap and rare nipple snap.
The color finish doesn't change a thing...
The cheapest from Taiwan and China will rust in just one season.
You could try titanium spokes but they ain't cheap and will break periodically making it an expensive hobby.
=8-)
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5000+ wheels built since 1984...
Disclaimer:
1. I do not claim to be an expert in bicycle mechanics despite my experience.
2. I like anyone will comment in other areas.
3. I do not own the preexisting concepts of DISH and ERD.
4. I will provide information as I always have to others that I believe will help them protect themselves from unscrupulous mechanics.
5. My all time favorite book is:
Kahane, Howard. Logic and Contemporary Rhetoric: The Use of Reason in Everyday Life