I used to do this type of work for a living, but I didn't use this SEM product but it was heat cured. Your prep work and cleanliness is the most important thing here. In the vid to me looks like he could have put another layer to hide it better. Like with any repair, it's a repair, and is well hidden by how good you are at the doing this type of repair, you could have a scar. Just how bad it looks is the question, as well as color matching. I have done repairs that have had scars but the customer was happy to have it fixed at a lower cost than replacement. After a few months I would check to see if they were still happy with it, after some use and dirt and a little wear you had a hard time finding where the repair was. Good Luck