As of now, I haven't known anyone who used or teached their child EK. Because in our place, early childhood education is very new. But what I already knew is that my son loves it and for a child that is 2 y/o, he knows so many for his age.
Many of our friends are amazed with his abilities and his knowledge. They even admitted that their kids who are 2 years and 4 years older than my son don't know the things that my son has already knew.
That's so inspiring! That's one of the reasons why I continue doing it.