
I have read your message and the replys to date.
The reason Jo says most responsible flatcoat breeders would say you should not have two young pups together is that it makes them more difficult to train. The result being that one or sometimes both end up in rescue. Both the breeds you have chosen to enquire about are very intelligent and are to all intents and purposes still bred with very strong working instincts. This makes them a handful to start with, but two together would "egg" each other on, and they would become more dependant on each other rather than you, so they are less likely to bother to learn anything you might wish to teach them. (This would include house training). Having kept both breeds, I know that as an experienced breeder and handler even I would only take on one puppy at a time!
I know that as a breeder of either breed I would be asking why two? Is it so they can keep each other company while you work? What do you want them for, working or pets? If the answer to the first is yes, and to the second pets, you have to ask yourself, would you as a breeder sell two such potentially clever puppies to this home? Especially knowing the likely outcome, for the puppies and for the people who have to make the heartbreaking decision to part with their pets?
As responsible breeders we do encourage new owners to be aware of any problems they might encounter, and would try to help them if they found themselves in such a situation. This is the reason Jo posted her second reply and I hope you will think about your choices before buying any puppies. Do let us know what you decide to do, as we are not against you having puppies but would like you to get the best from a potential puppy you might decide to own.