Knives that have an Iron Cladding are the most reactive and susceptible to rust and discolouration. If any part of the blade is left wet or left in contact with something containing any amount of moisture these blades can and will rust. We generally only recommend these knives to the most meticulous of users, whether you're a professional or home cook doesn't really matter, what matters is how diligently you will wipe down and and care for the blade. With that said, all that needs to be done to avoid rusting is to wipe the knife down immediately after use. Furthermore, with proper care a protective layer called a patina will form on the blade turning it dark grey and even close to black in some cases. Additionally, If any rust should form it can be easily  removed using a rust eraser, baking soda paste, or an abrasive scrubby pad. Iron clade knives are also tons of fun to sharpen and if you're a real deal knife nerd you will have tons of fun sharpening, thinning and polishing these knives, they react favorably to high grit and natural stones.