I like to use both mallard and bluebill dekes. I usually put out a ball and chain pattern for my bluebills (kind of gives ' em a landing strip) and a grouping of mallards. I leave an opening in between and place my spinner in the opening. Just this am I had a goose land in the ' bills and a few goldeneye land in my mallards. The ' bills seem to be more visable from a distance and the mallards seem to have a calming affect up close.