I noticed that he sells smooth and curly breasted sebastopols, which 'variety' did you get?
That's another issue too. While the smooth to curly Sebastopol breedings are common in England, for various reasons, that does not hold hold true for most of the quality stock in the US. He is the only person here who claims this. Most Seb breeders breed curly to curly for generations, with no issues. Some see the claim as merely a way (excuse?) to justify selling Seb goslings that mature without curly breasts.
There is no one waterfowl breeder who has or claims to have as many show quality breeds and varieties as Holderreads. Many are small and local. Few are set up as commmercial hathceries, to ship day olds on such a large scale as Holderreads. Gary Overton is supposed to have nice Sebastopols. For most other geese, Ryan Gartman in MN has great birds, including some quality ducks. There is a very small breeder in New England, Bonnie Cavanaugh, who has some of the nicest Brown Chinas I've ever seen. James Konecney in IL has the best Aylesburys, there are half a dozen or more great Call breeders: Art Lundgren, Evy Avery, Lou Horton, Charlie Hodum, Walt Leonard, Twisted feather Farm, there are others. Chris LaGeroud is the man for Cayugas and Indies.
Like was said, if you have your heart set on them, still go for it. I never said that no one was satisfied with birds which came from there. In recent years, the only ones I've known to be very happy have been those who have bought Africans, or those who aren't interested in show birds, and so are happy with whatever pops out of the box as long as it's the color it's supposed to be, it's alive, and it lays eggs when grown. I may see the cautionary side of things rather than just swallowing whatever I'm fed, but don't take my word for it. Ask around on some of the other forums, and see the responses you'll get from multiple people. And do some research, and try to find a single speck of evidence that the claims of old or multiple species ancestry that I question are true. Just because you read the results of a good marketing program, doesn't mean that it's not hyped or twisted specifically to sell more product.