You should bear in mind when buying any KC reg dog that anybody can register their pups on the KC website for sale. This does not necessarily mean they will all be of the same quality, even though they may have good blood lines back in the pedigree. As I said on my previous reply, you really need to do your homework and go and look at the pups yourself. Their housing and the owners will give you a good idea of how well they have been bred, and as someone said to me recently, the way the pups are reared and what they are fed and how they are looked after also plays a big part in the puppies growth and progress.
I recently looked at 2 litters of pups and found one to be an outstanding litter and the other was nowhere near the same quality, even though the stud dogs for both litters were from the same breeder. The outcome of the pups cannot be left down to one of the parents, they must both be of good stature and be a fine specimen of the breed as well as having responsible owners that are knowledgable of the bulldog breed and preferably have a good background and experience of bulldogs.