And Sasori could destroy a whole country with red secret. But his Granny and Sakura beat him. It's okay to have doubts when they are founded.
Plus with Diedara Kakashi and Naruto nearly sent him into the next world. If Naruto had been able to go 3 tails and definitely 4 tails Diedara would be a lump of burnt clay.
I wonder when we get to know more about this Uchiha Madara the Kyuubi was talking about, I hope it's the Akatsuki's blue haired unknown member
I just wish that sharingan would lead to terrible disease which would lead to all remaining uchihas death (sasuke, itachi, madara, even though it would mean kakashis death). Thanks to that we could forget about "bring sasuke back, datebayo mission" and all "uchiha has a dark past" theory.