I think it is great that you came here and are asking questions first before you buy a "Giant Doberman"
But there are plenty of Giant breeds that have existed for years that you could choose. Why not a Great dane, Mastiff, Irish wolfhound, even a Rottweiler? As far as a Great Danes getting a twisted stomache or bloat that can happen to any dog especially the "GIANT" breeds so Giant dobermans can be just as much at risk as any
. Also as far as life expectency they say the bigger the breed the shorter it's life, although I also think it depends on how you care for them that makes the longevity of life longer. I really hope you do LOT's of research on what you are looking for and personally I would rather go for a well bred Dobe or great dane than get stuck with a"designer breed" that could potentially suffer from problems and that's not to say that purebreds don't have problems or health issue's to worry of, but If you go to a reputable breeder of one of these breeds that is breeding for the betterment of there breed and do all the health checks that are necessary for the proper breeding of the best possible specimens than chances are you are going to get a beautiful healthy litter of puppies with little chance of genetic or health issues. And also remember BIGGER isn't always better!
