I dont even like Kabuto but he can pretty much destroy almost anybody. Prime Kabuto is pretty powerful himself but his real power comes from his impure res. Even if he went up against Madara (which he wouldn't be) i doubt madara could
defeat a couple dozens of the most powerful characters of the narutoverse. For ex most the akatsuki, the jinchuurikis, the kages, gold and silver, and many other powerful ninjas.