I would not take 2 littermates for ANYthing, honestly. Not only is it twice the trouble (maybe more, as they'll be getting into trouble together), its twice the costs, and as Dixieland said - if there are behavioral problems that show up when these two begin to mature, it will be twice the WORK and struggle for you! Unless you're home a lot, and you have tons and tons of time and experience, I'm guessing that no matter what sex they are these pups will bond to eachother. Just imagine taking 2 super-hyper puppies to Obedience together... !

My advice would be to (1) keep the pups until AT LEAST 8 weeks of age, PLEASE! If not, their social skills with other dogs and people (especially because they're large dogs of unknown lines) will be severely affected. The future temperament and socialization of dogs in their adult stage is based heavily on the socialization they recieve from 8-16 weeks, the longer you keep them together, with mom, and around tons of people, kids, animals, and positive experiences (ideally until 12 weeks), the better adult dogs they will be. (2) Keep one puppy, unless you truly feel you can handle 2 pups and are willing to seperate them quite a bit for a few months so they can bond to you. (3) ONLY place these puppies in screened, loving, experienced homes with people that are fully willing to go through tons of socialization and puppy through adult Obedience classes. Adopt them out on a Spay/Neuter contract, FOR SURE! You do not want these puppies to be reproducing, as they are from stray and temperamentally unstable parents and they do carry those genes. On top of them not being even close to purebred or well-bred . (4) If you cannot find suitable homes as described above, which does happen, find a very reputable (no-kill, screened adoption, foster home) rescue in your area/state. They will most likely take puppies from you gladly.

I do understand that some people have success with 2 sibling pups, but unlike k9krazee and woman, your dogs will be 80+ pounds... keeping 2 80-lb dogs in line is WAY different from keeping 2 Jacks or Lhasas in line.