You don't mention what your budget is. IMHO without a doubt good cork decoys are the best cecoys on the market. One's like those sold by LL Bean. I hunted mostly public land and can tell you a dozen of those are better than 2 dozen of anything else. This opinion is based on 42 years of waterfowling. Details aren't needed in decoys simple is better. Cork rides better and looks more realistic. They do not look like fishing bobbers in the water when the wind picks up.
The down side is they are expensive and heavier than most other decoys.
My second choice is the herter style molded foam body decoys.