IMO, the advantages both Aldo and Barao have at their current weight would be marginalized when they start going up against larger weight wrestlers, who will be huge in comparison.
Matchups like Aldo vs. Gray or Bendo or Barao vs. Mendes or Lentz would exemplify why these guys are at lower weights to begin with. Grappling is such a huge part of MMA and I see these guys having difficulty against bigger athletes who will be able to suffocate their attacks.
MY MMA RANKINGS
HW Velasquez Cigano Werdum Cormier Bigfoot Barnett Mir Browne Nelson
LHW Jones Machida Evans Hendo Davis Goose Teixeira 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 Maynard Melendez Thomson J.Miller Diaz Pettis Chandler Grant dos Anjos
FW Aldo Mendes Curran Lamas Frankie Zombie Cub Lentz Kawajiri Siver