This post will link to the feedback threads that are no longer stickied. Please post in the thread if you have feedback for the bosses in 25 player Heroic difficulty.

Morchok
http://us.battle.net/wow/en/forum/topic/3424910356

Yor'sahj the Unsleeping
http://us.battle.net/wow/en/forum/topic/3424690202

Warlord Zon'ozz
http://us.battle.net/wow/en/forum/topic/3424910357

Hagara
http://us.battle.net/wow/en/forum/topic/3580918170

Ultraxion
http://us.battle.net/wow/en/forum/topic/3424690203

Warmaster Blackhorn
http://us.battle.net/wow/en/forum/topic/3580988165

Spine of Deathwing
http://us.battle.net/wow/en/forum/topic/3580988166