There are two body types of labs. The American LAB "Typical Type", for the most part, has longer legs, longer nose. They are taller in appearance, and have a longer skinny tail. They are not as stocky as the English "Show Type". The American dogs are larger dogs, overall. They have a longer neck that is not as thick. On the other hand the English, for the most part, have a shorter, stockier frame, shorter, thicker legs, a shorter tail, thicker, shorter necks, shorter nose and a much blocker look to their build.
I like a little of both that is why I do have a little of both in my dogs .. WHY >>>
The English being shorter leg cant keep up on the farm, and my Horses, they might be pretty in the show ring. but they can't keep up with the kids they wear out to fast. They are only good for 2-3 hours of work if that and that's one that is in shape not a show dog
The American being longer leg can go and go all day ether running with us on Horse back or the 4 wheeler's, tossing the ball for hours (great play for the kids) but I do like a little bit of the English head. Your American are the ones that sit all day in a duck blind (being good) waiting for the hunter to shoot, can't have a hyper dog there.
I need a dog that can go all day and night if needed working around the farm and on guard duty for the night watching over the family. AND a mix of the two was just what I was looking for. NOW this IS my opinion. You might find some great English dogs out there, but after 30+ years raising labs on the farm I need a dog that looks good and can keep up with me and my grand kids on the farm I need a dog that can go 12-14 hours a day every day. I don't have the hip problems because my dogs our out moving on the farm not locked in cages and kennel they run the play like dogs are meant to do. not locked away. and they come in the house lay down and be good. I have 7 lab's in my house that sleep on or by my bed