Well Tobi is definetely stronger as he also has Senju cells and does have some crazy physical strength feats. It is taking three high level ninjas to put Tobi down and Sasuke doesn't have what it takes to beat Tobi on his own. Well he can hold his own against 3 tomoe Tobi but he is going to get warped. Those projectiles are a threat too but Sasuke could use susanoo.