Purchased with the advice of a friend who saw him in action on an ADHD child, I've been tempted, my son almost 5 years of being unable to sit without gesticulating, it sometimes ends with feet on the table! we spend our time asking him to sit down properly, it is exhausting! well ...
it works! it's crazy and it changes our daily life, the more he must feel that it helps because he loves "his cushion."