With ferro rods, stainless and carbon both work fine. The deciding factor is the hardness of the blade, because its only job is to scrape bits off the rod and create enough friction to make them sparks. With flint, on the other hand, the sparks come from the metal, so I don't think stainless does work, though I've never tried.
Originally Posted by happybonzo
I find edge retention to be much better on Carbon, and I also find it to be much easier to sharpen.
Stainless, of course, is often better if in really wet conditions, particularly seawater. My dad doesn't like using a carbon kitchen knife I made on onions, because it discolours them.
I have a couple Moras in stainless and several more in carbon - the stainless is good, certainly better than any other stainless blade I've seen in that price region, but I still prefer the carbon. It also develops more character with age, which I like
At the end of the day it's down to preference, really. I'm willing to put in the work required to stop my carbon blades rusting, and I like the patina they get. Some people will consider the lower sharpenability worth it, for the corrosion resistance.
Hope this helps!
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