I think it should be left upto the breeder to pick since the breeder spends 24 hours with the litter , analysing the dogs , their relationship with other litter mates etc etc , As far as show quality pups are concerned , it all matters with how well he combination does and wether they dog and the bitch click or not , i would say that at an average of 1 to 2 show quality pups should be present on a reasonably well bred litter assuming the breeder actually spent time anf gave thought to who he breeds his female to etc . There are some breeders that breed for consistency and can get some pretty serious quality overall from their linebreedings . I posted a pic of my brother's dog some time back (pluto's dad) , from that litter my brother got MOUJI (multiple BIS and BOB winner) , Jadoo ( Ind Ch. and BOB winner) and 2 females that half about half the required points towards their titles so that gives something like 4 pups out of the 9 pup litter that turned out to be very very competive in the show ring .
Great answers here. One has no idea on the depth of quality on a litter until they are aged, at least six to eight weeks anyway. Some litters you have a great even high quality and easily a few potential prospects...others...are a wash out. Doesn't matter if the parents are multi Ch's with great wins or just one title, its all in the type of breeding and how the dogs have been bred. Outcrossing sometimes give you one standout puppy, close linebreeding on a closed bloodline will give you cookie cutters and sometimes its splitting hairs to choose. And then sometimes you throw the book out the window and the ugly duckling at 8 weeks looks like Miz America at 3 yrs. of age.
Given you situation, you will be in a wait and see spot. If one bitch out of three had a bad bite or other bad fault, you would be getting your pet most likely. Breeders are breeding for themselves first, pet people, very valued, have to understand that and you must wait....we do this for US not you primarily.