Fishking knows his stuff. His fish are healthy, none stunted nor do they have bent spines. He has them set for pure breeding and not public display. The numbers he has in a tank is nothing compared to some other breeders and oversea breeding farms.
I own 95 fronts of various types, i have them set for display/breeding and get reasonable results. In a 4x2x2 I have a small colony of 6 Burundi between 18-25cm 1m 5f. When I added the last female, the colony became a lot more peaceful, not as easily spooked and they all breed a lot more regularly.