I have owned 5 American Brittany since 1991 and picked up my first French Brittany in 2018. Both breeds have similar traits regarding training, handling in the field and around the house. All my brittany were full of energy in the house until they were close to 4 years old. If you worked their minds, they were calmer. If they lack exercise, they had more energy. My decision to go with a French was twofold: 1) my long-time breeder of American Brittany passed away 2) my hunting party went from 4 down to just myself. My French Brittany tends to work closer than my American Brittany. However, he will get out there depending on the terrain and cover. As far as the cattails, I had a similar concern on their size. However, my French will bust through cattails as needed. With that said, if the cattails are so dense that I cannot walk through it, my French cannot bust through as well. This was similar to my Americans. I have never hunted behind big dogs in cattails (GSP, Labs, Pointers, etc.) and I have no comparison. The biggest difference was in the retrieving of pheasants. If it is a big pheasant, my French does have a tough time of picking up the bird and carrying it back to me. He tends to grab it by the wing or the neck. Good thing, he does not dig his canine teeth into the body of the bird. Bad thing, if it is not a clean kill, he will just stand on the bird until I pick it up. The other difference is his personality. He wants to be by your side constantly and wants to lay next to you when you are on the couch or in your chair. As with any new pup/litter/dog, the parents and genetics need to be thoroughly vetted. My American Brittany were from 18”to 19” to the shoulder and ranged from 40lbs to 50lbs. My French is 17” to the shoulder and 35 lbs.