my son is almost 3 and he's very much into painting. I bought these colours as they seem a good solution to avoid general mess. In this, they fulfill their goal: you don't need additional brushes nor water, and the paint comes easily away from clothes and skin. However the experience is a bit frustrating for a baby painter, as the brush is made in plastic (not very flexible). The result is that the baby squeezes out the paint in a stain and tries to spread it, generating a semitransparent line, without any control on the result.
Maybe better sponges instead of the plastic brush.