I'm a huge Mousasi fan, but I think it would be far more adventageous for Mousasi's career if he made the cut down to MW. That's not to say he could beat Anderson, but he's got an amazing skillset.
MY MMA RANKINGS
HW Cain JDS Werdum Cormier Barnett Bigfoot Overeem Mir Browne Nelson
LHW Jones Machida Evans Hendo Goose Teixeira Davis Shogun Mousasi Bader
MW ASilva Belfort Weidman Jacare Okami Rockhold Kennedy Consta Bisping Boetsch
WW GSP Hendricks Condit MacDonald Diaz Maia Fitch Kampmann Ellenberger Pyle
LW Bendo Alvarez Grant Melendez Thomson J.Miller Diaz Pettis Chandler dos Anjos Gray
FW Aldo Mendes Curran Lamas Frankie Zombie Cub Lentz Kawajiri Siver