Just be very careful if younger children are around when playing with the magnet balls.
A few years ago children that were 6 and younger were swallowing the magnetic balls. If only one was swallowed it wasn't a huge deal but some children died because the parents didn't know they swallowed them and it caused there intestines to stick together with the magnets.
I believe the age on the toy was 5+, but there was a child that was in the recommended age group that swallowed magnets.
They may have made it so the magnets aren't as strong.