We have three kids in the program. Chris, Candy and the rest of the instructors are top notch. Maam Cindy can keep 20 4 - 6 year olds more in line and disciplined than any other person I've ever seen. We're 4 months in and the kids still love going 2X+ a week. The promotion system is fair and they do force kids to get things done and learn. They don't just push them along (although they're not too hard on the little ones).
The things they teach at CGTKD are things kids don't learn elsewhere. Discipline, Respect, Honor, Intensity, Power, Focus, etc... A must do for all young kids, IMO and great for the older ones who want to go somewhere with it.
The class sizes are around 20 each and the Dojoang is not that big (only negative I can think of), but the make it work and make it work well. There's almost always 3 - 4 instructors for every kids class.