[Prot Warrior] Is The DMF Immortality Trinket Worth?

[LethalPotato]

Title, I heard that it's really good for physical damage reduction, however i'm just wondering if I should get it, Mr Robot also says it's good but I can't decide whether it's actually worth getting and using and at what point should I replace it?

Bonus Question : There are some pretty interesting trinkets from the cata time walking event this week, are any of them good? (In particular the "get 11k armor when you drop below 35% health" trinket)

[Valech]

Title, I heard that it's really good for physical damage reduction, however i'm just wondering if I should get it, Mr Robot also says it's good but I can't decide whether it's actually worth getting and using and at what point should I replace it?

Bonus Question : There are some pretty interesting trinkets from the cata time walking event this week, are any of them good? (In particular the "get 11k armor when you drop below 35% health" trinket)

timewalking trinkets are getting nerfed with 7.1.5