The copper finish on the outside is very nice. The nickel plating on the inside is the concern. After a few uses it has faded to reveal the copper underneath. We went back to the reviews and found others who had the same issue. We found one that stated the finish was supposed to come off. If this is true why doesn't the manufacturer state this along with the best way to remove the nickel finish? One should not have to guess what to do meanwhile ingesting the nickle that slowly dissolves in each drink.