My friends are on their third flat coat. All bitches. Max 2 at a time, now down to 1 again.
First: black (the 'usual' colour), really well trained, one of my friends was an ex-RAF dog handler and really put the effort it I believe. Very driven, almost neurotic, loved sticks and the sea more than life. Would jump into bramble patches if you had poor throwing aim, and stand in the sea shivering refusing to get out.
Second: liver (also breed acceptable, but recessive), less effort into training, sort of let the older dog show her the ropes. Could not be arsed to fetch. Stubborn, lazy, lovely, licky, not a fan of water.
Third: liver again, the stupidest (and I love her, I really do) dog I have ever met. If she's stubborn instead she's the worlds best actress. Clingy, whiney, absolutely rules my friend now her partner has gone. Loves water, no danger sense. Higher energy than the middle one, but much less focused than the first.
I think they thrive either with one very hands on person who is their primary focus, and does a lot with them, (and they will be stubborn for everyone else) or in a very busy household with other dogs. I think to some extent all dogs adapt to their environment, but we do joke that the brown gene is also the stupid gene.