Well, they are worth it for kids who make a mess everywhere because they come off easily, but they are also worth it for someone who is a beginner and wants to paint on objects but is afraid that the object will ultimately be ruined. For example, I paint dolls, figurines, and decorations. I started with these, and whatever mistake I made, I just rinsed it off. Of course, I didn't leave it for many hours to see if it would leave a stain. However, be careful, they have nothing to do with watercolor pencils that, when dry, do not come off. So if something you painted ultimately pleases you, you will need to seal it with some topcoat.