I’ve just conducted my own coin test of the enamel during the process of writing a review on a Miele W 3740 washing machine review, which involved hitting it very hard with a pound coin.
First I hit a normal appliance (not very hard) with the coin a couple of times, which clearly takes off the paint right down to the metal. Then I hit the Miele washing machine (increasingly hard) many times and it doesn’t leave even a feint scratch.
I must admit, I hesitated a little before hitting the Miele with the coin, it was a brand new washing machine and it seemed to be asking for trouble. Nevertheless the Miele direct enamel coating lived up to its promise. It’s extremely tough and would easily resist knocks from kids for example.
See my video –