as once the pads bite into the rotors the zinc coating is removed from the rotor. Your hubs shouldn't rust if they are zinc coated (assuming you don't use some harsh wheel cleaner that removes the zinc coating sometime). Stainlees steel brake lines are supposed to help with a mushy pedal as the lines don't expand like rubber does when the fluid is under pressure. I really didn't notice much of a difference (but I drive like a grandmom).