guess the same as most of us do. you can only go by what you fancy if you fancy them as racers put them in the basket and see,and if you fancy them as breeders breed from them and see the results,there is no 100% sure-fire way not in this game.
the RSPB have brought this on themselves with all there lies the public are needing to waken up this will happen more and more[i don't condone it] but I can understand it
very difficult to keep them out of the gutters especially if u live on a housing estate try giving them mixed grit and pick stones and keep them in for a week my birds wont eat red grit young birds will always pick about no matter what u give them. good luck
JOHN if you recall a number of years ago the fed had an extra race you won it and I was second no prize money or winner cards . so I doubt if the extra race will count in the averages, in fed or club.