This is a really old post, so I hope you are still interested in the breed?
I can give you some first hand info... I have a briard now for 1,5yrs and my mother also has one.
So I'll try to state the things you might not read in all of the briard descriptions.
they come in 3 colours, fauve, gris and noir, which means a light orange-like-brown, grey and black.
Grey briards can be either born grey (this is very rare) or become grey over the years from a black pup.
(Elliot is 20 months old now and already has a lot of white hair)
He has a very calm character, he is used to come to uni with me and he would lie under my table for hours without any problems. I haven't ever trained a BC yet, but I think briards are very smart too. He loves to learn tricks and he is not too bad in dogschool.
To me, of course, he is the perfect dog...
BUT he tends to be a bit over-protective, I think they have a strong sense of what belongs to their territory and what doesn't. Elliot didn't let anyone pass the trunk of the car, or enter the campervan, or the house if I wasn't there.
I was quite shocked when I realized that, but now I found a nice dog trainer that also does protection training in a really nice way, so we are working on leading that behavior to something that he can put his drive in when asked to do so.
He loves people, but he makes a difference between people that are together with me, and people that I don't know.
His mother and sister are both trained to be therapy dogs.
He is a very social dog, but I would consider him as rather dominant against other male dogs, but I guess you cannot say that for the whole breed. I knew what I was buying because Elliots father ( the black one at the bottom 2) is also quite a leader
And you could also tell when watching the pups. But I never had any problems with smaller dogs / females.
I have seen the videos of Norman, the scooting dog, who has his ears cut, in the EU this is forbidden since a couple of years, Elliots father also still has the standing ears, but I like the hanging ones better.
Elliot is fun to work with but he is not a very high drive dog, so he likes playing and working with me, but he is not overexcited over a ball or sth. This is not really helpful when you want to do competitions or so, but I guess its better for the dog's nerves. I am not too sure about getting too ambitious with your dog anyway. I guess that there are breeders that are more interested in breeding high drive dogs, but I got mine from a really nice breeder that tries to breed nice family dogs.
(When I got him I didn't know I was going to get so excited on dog training)
If you really consider a briard, be aware of a lot of questions you are going to be asked in the streets. They have a really beautiful appearance and people tend to be excited about that. This is nice if you want to talk to new people all the time, but there are times where you might feel like you are not getting anywhere without answering the same questions all the time
In terms of grooming I would consider maybe one or two hrs a week, if you want a neat appearance. My mother wouldn't take the time to groom hers so often but then they also cannot develop the long and silky coat that they are known for. I think the worst thing is if you have to cut their hair because you cannot manage to groom them often enough.
In terms of activity you should really give them a job, we are in dog school twice a week and next to that we go with the bicycle, rollerskates, sheep herding, tracking, agility, well everything that makes fun.
I would say that briards are great all-round dogs that you can do every sport with. They like everything their owner would enjoy. And they always want to be around you. Since they are really clever and intepentend in taking decisions, they also get bored from repetitive tasks pretty soon.
They are known to be very couragous, and for Elliot thats true, I didn't find anything yet that he is scared of.
(but this also goes to the breeder, she did a really good job during his first weeks)
Briard are really nice with kids, I have 3 really small siblings and he is adorable when with them.
In conlusion I would say that if you have enough time for dog activities and grooming, they make a perfect dog.