DD’s working cocker doesn’t get in a mess eating, just whenever she’s outside!
Cocker “rage” syndrome certainly has not been bred out of them and there’s a real problem particularly with show cockers, but also, increasingly, with golden retrievers AND some other red-gene gun dogs (vizlas, gsp). Few people who shoot will work chocolate labradors, they just seem to be wired differently and aren’t as steady to train. If you have Facebook it’s worth following Perthshire Gundog Rescue, they see first hand the endless problems of pretty puppies getting taken to the vet for euthanasia after aggression - show lines especially, though not exclusively (and I don’t know what lines they are).
I’d only ever get a puppy that has been reared in a family home, not in kennels, as lots of gundog breeds are because working dogs often aren’t kept in the house. If the dam is a family dog used to children and the bustle of a kitchen, she’s more able to rear puppies with confidence around people.
I have had dogs given to me as adults but they’ve all had ingrained issues. My late MIL always adopted “rescue” dogs and they were usually in rescue because they were awful to live with (eg habitual escapees, destructive, noisy…). Get a well-reared puppy from an intelligent, kind breeder who cares about the breed and guarantees lifetime interest and support.
Good luck!