When you're using cheap materials, you're always wondering "what's the catch?".
With these acrylics from the euro store, it's that the don't completely dry lightfast and so the layers drag into each other as you wash one colour over another - oh! and the fact that the colour selection is the pigment equivalent of chocolate "flavoured" candy bars.
Anyhow. I got my €2 euro's worth. The kids will find some use for them.