Even if Chelsea Grin were on their A-game, they'd be a questionable choice. But their vocalist has completely blown out his voice. If you see recent live videos of them it's pathetic.
Same with Emmure.
Miss May I might be entertaining though.
10/17 - Machine Head/Battlecross
10/31 - Killswitch Engage
11/28 - Slayer/Exodus/Suicidal Tendencies