Even with DSM, Kabuto resorted to using offensive Medical Ninjutsu, something Tsunade & Sakura seem to not use due to wanting to use their super punch ability
Yes he is without a doubt. Also mystic palm can go wrong if the user isn't careful and Kabuto has shown the unique ability to use a long distance mystic palm. Technically he could use it like a whip that destroys what ever body part it hits or as he did to kiba in the chuunin exams render then unconscious.