does having c.s.a have any differece than basc. i have been looking at the decoys on the market and they seem to sell either single or in packs of 6. the 6 packs vary from 1 hen to 5 cocks and all 6 hens. what is the best pack to buy for decoying ducks, if you have a a varity of ducks coming into the ponds is it best to buy just pairs of decoys and overal have a mixed decoy paterrn