I can't see where a reputable breeder would have need of a CKC (Continental Kennel Club) dog. Many times people get dogs with limited AKC registration, then get CKC registration for breeding. We have one woman in our state who did this, then advertised that the parents were AKC champions. Of course the breeder who sold her the pup made the first mistake when she didn't require spay/neuter.
I've been told that all it takes to register a dog with this CKC registry is a picture and two people signing that the dog is in fact that breed. I have often joked that I was going to register one of my big rescue dog as a Maltese, just to see if I could do it.
Personally, I'm a firm supporter of AKC. While it, like everything else, is not perfect, it does offer us a way to keep a record of our dogs. I want to know what is behind mine, which I can do with AKC. With the DNA testing, there is a check and balance for frequently bred dogs. None of this is offered through the CKC registry puppy millers use.