Never buy the inferior stock. You can't truly be certain if any problems you see are due to genetic deformity, malnutrition when much younger, or if it is caused by damage from toxic levels of ammonia during the early growth stages.
Distributors will learn not to accept inferior fish from breeders; and breeders will learn to take better care of the progeny they provide.
Problem fish hardly ever "fix themselves with better care" and almost always fall short of the potential they were born with. More often than not, you will not get lucky with the inferior fish and the money wasted on inferior losses and maintaining "the survivors" could easily have been applied to better purchases (with patience) and with less hassels during their lifespan.
Common problems associated with the inferior specimens (besides the deformities) include more prone to disease, tumorous growths, shorter lifespan as compared to others of their species under similar conditions, and a biggie... sterility of the inferior specimens moreso than the less and non deformed of the same species. That my friends is a death nail in the future of this hobby for any given species bred to the levels of rampant deformities.
If you are willing to purchase crappie fish (and I don't mean bluegill and perch), your LFS will be more than happy to acquire them for you by the hundreds. You all know a good fish when you see one. Don't sell yourselves short. This applied patience will also help keep you from overstocking a tank so fast and you will usually be much happier with the long term results.
Do you really want a deformed or inferior fish for breeder stock? People do want to know what the parents look like.
OK... so you don't plan on breeding them. Where will you stand if ever you change your mind and you have inferior adult fish?