These are great for craft time with my toddler at home. She loves the different colour and how easy they are compared to her pencil crayons, which require pressure when colouring.
One day she happened to walk by the wall with the purple marker, leaving a wavy line about two meters long on our white wall! GASP!!! Luckily, all it took was one nappy wipe and within seconds it was removed. We noticed it straight away, not sure if it would have the same result if left to dry for hours/days.
The only negative is that she finds it a bit difficult to put the lids back on.