Depends on the situation. If your hunting early season birds that may not be flocked up yet smaller spreads will due the job. Late season birds tend to sit in larger groups so more decoys will work better. Observe the flocks that you are hunting if they are in small numbers use a smaller spread and vica versa. Also if you are hunting in a place where your decoys may be hard to be noticed use a larger spread. Use your best judgement.