It looks good. I wonder if it's really 420HC stainless--stainless usually doesn't react that quickly to acid, especially something as mild as vinegar.
I see that you have it up for sale--if this is made from a blank that's okay, just make sure you are up front about it with potential buyers. It's accepted in Europe that "handmade" knives are made from bought blades, but here in the U.S. and many other areas the assumption is that if you claim you "made" the knife that you made it yourself by either forging or stock removal. Knives made with bought blanks are not typically accepted as "handmade" or "custom."