It's perfectly fine with stainless and I never had problems with 2 of my C-steel blades. I'd rather use that stuff than Barbacide, which is (according to hair care professionals I discussed this with) only to be used on combs and other plastic items.
However, if your blade has lots of pitting, then Joe's admonishment is certainly valid and I'd use another way of sterilizing it, like clippercide.