Magic Erasers are abrasive, so avoid using them on delicate countertops such as marble and granite. Not only can you damage the sealant but the eraser may make the countertop appear dull. All of these cleaning products can cause more harm than good.
If you scrub your stainless steel too hard with a Magic Eraser, you can actually make it look more dull. If your stainless steel appliances have scratches, try sanding them out instead. Try these stainless steel scratch remover tricks for appliances.