I am from Kansas and have had working line GSDs for almost 25 years. Never heard of them. A few red flags for me with any GSD breeder: no real working titles, not even in UKC performance events, I believe you can get your UKC confirmation championship and never beat a dog of your breed,and a real mish mash of types of GSDs. There is a breeder in the McPherson area that I know of that also breeds a more "family " vs working GSD. She also does not title her dogs and often mixes types. But her prices are fair and she does every health test she can on her breeding dogs. Knew her mom slightly through out local AKC club. I would end it with if that kennel is producing the type of GSD you want, and you have talked with them and feel good about them, that is what counts the most.