Personally, I think Fedor will beat Mir because Mir is so out of shape. I cannot see him having a productive camp considering he will have to focus on making 265....which is pathetic considering how in shape he used to be. Fedor will probably be around 230 lbs. and Mir will be like 263 with zero cardio. If Fedor dances around for the first few minutes he can probably put Mir's lights out.
As for Sonnen, I don't know. He doesn't have KO power and I think Fedor can catch him as well. I think Fedor will reach the finals.
However, I do not see him beating Mitrione, Nelson, or Bader at this point. He would have to get lucky and have King Mo reach the final due to an injury or huge upset(s).