Big, clumsy, short lived, expensive to feed and rear corrrectly as puppies and adults, do large poos, need bigger dog beds, bigger kennels if you ever go away, bigger vehicle to transport them, more expensive to treat at vets, liable to gastric torsion (bloat) which is life threatening, need stronger collars and leads, in fact everything about them is bigger and more expensive! They can however be great fun to live with and if bred correctly are great with people and other dogs.