If you want a dog to be used for hunting, make sure you buy from a breeder that hunts with their dogs. Most Cocker Spaniels today, at least from show breeders, probably have little to no hunting drive in them.

It also depends what type of hunting you do. Differen't dogs do differen't things. Labs are retrievers. Cockers are, most definitally, spaniels. Beagles are hounds. Each "type" does different things.

You also need to take into consideration ease of training, good with other animals, size, and other tendancies....do research on all of the breeds you are interested in. Contact their breed clubs and ask for breeder referalls.

Good luck with your search!