We got introduced to this product from a family member from Germany. He is a professional juggeler and uses this at work. Both our sons ages 14 and 7, fell in love with this toys action right away. Within days the oldest had lots of tricks mastered and the youngest did too!
This product although smaller than the version that our friend brought from Germany (we knew that) is well worth the investment and there are lots of videos online to teach you tricks. 5 stars

My son saw his classmate playing with diablo and was waiting for it to arrive eagerly, he played for hours and still plays with it from time to time and still enjoys it. 5 stars