The powder is somewhat harder to use on knives, but the price difference is staggering. I put a little in a bowl or demitasse saucer with a couple drops of water and dip a (real) wine bottle cork in it. I rub my German and French knives in little circles until I'm satisfied, rinse, then do it again with baking soda to neutralize BKF's oxalic acid.
Edit: sorry, I already forgot the OP... baking soda isn't totally necessary on real stainless steel (like sinks or All-Clad and similar cookware), but avoid using BKF altogether on lacquered metal like some SS appliances and kitchen tools, and coated brass and copper. Also keep it away from anodized aluminum (including all *lon cookware). The baking soda neutralizing step is for carbon steel and iron, to avoid acid etching or discoloration.