I've got two characters making use of Unyielding Sentinel

Warlock Tank using celestial mandate epic strike ( upon reaching 30 will switch between shiradi and unyielding mantles as needed )
Paladin Vanguard using the Unyielding mantle

Celestial Mandate: The PRR/MRR effect last 10 seconds not 15 and the entire stack disappears should the top member of the stack expire. It makes it very difficult to maintain. Roll a 1 and miss and the stack disappears shortly after.
Knight's Challenge: At 20 second cooldown it is way to low damage to be an effective offensive weapon. However as a aggro reset it works as advertised.
Hands of the Sentinel: The ability to use constitution instead of charisma is a big boon for my Strength based vanguard.
Spark of Life: Having this at a post-req for Knight's challenge and a pre-req for throw the boom is very annoying since it has nothing to do with either.
Rule of Law: Damage seems low. If you're a high speed melee attacker, it goes off at about a 10 second interval. My warlock tank though only 1 out of every 5 attacks is melee so the rate is much lower and not worth it.
Into the Fray: I see very little value in this ability, 5 seconds of minor buff once per combat?
Divine Bulwark: Any chance of fixing this so it doesn't require such a small subset of defensive stances?
Best Defense: My warlock Tank will end up taking just for the hp. But the question is .... what qualifies as blocking an attack? If it's the "block maneuver" then the only value in this ability is the hp as I either attack or block but don't alternate between the two.

Neither character is level 30 at the moment though the warlock tank will be there soon and take some Tier 5 then. The vanguard is going Tier 4 in Fury and Unyielding and will take Tier 5 in no destiny.
Gaining access to higher Tiers results in respecing the destiny as it tends to be a little top heavy.