I'm sure blades have been stainless for years, but actually high carbon steel can be harder, thus take and hold a sharper edge than stainless. However it does rust quickly, thus isn't used in razors anymore. If you have an old straight razor about as i do my grandfather's, it'll rust over pretty quickly. but when really sharpened on a razor stone and a proper leather strop, will be much sharper than a modern blade.
Not that i have the guts, or the spare blood, to try one on the old "dial" tom Fowle
