I have a few kids using it and they like it. Keep that video on your iphone, because blue WILL question you about the bat when they hear it hit a ball. Some will think it's broken, others (especially if the kid is a strong hitter) will think it's been modified, ect.
Love the video, my dd had an at bat last yeat just like that. Fouling the ball off everywhere. Just when you think the batter is getting tired, she cranks one to LF.