I've been testing it a bit on my standard CI Baron Zombie build. On minions that don't crit and do pure physical this buff its better than host chieftan for sure. Renewed my 4 support spectre setup to the following:

1. They of Tul - insane defense. It's nice because you dont get much dodge/spell dodge in minion builds. This just adds another layer to what you already have.
2. Carnage Chieftan - frenzy charges for the big damage, ramp up, clear speed.
3. Diabolist - big defense (with the rumored level 50 enfeeble it casts)
4. Arena Master - the attack speed is a big buff for pure phys. great for longer boss fights. the movement speed buff every now is a bonus once in awhile. In fact this guy feels like you are wearing a Saqawal's Nest without having one.