You don't gain many stats on any of the items you listed.
T7 vs.
Deconstructor Shoulders:
- +3 Sta (Solid Sky Sapphire in the Valorous)
- +16 Str
- +38 Armor
- +7 Defense
- +7 Dodge
- +43 Hit
- -39 Parry
In my opinion Deconstructors better stats outweigh the 39 Parry you gain with the Valorous. (factor in DR and 39 Parry isn't that much)
Bracers of the Knight vs.
Mimirons Couplings:
- -2 Sta (Solid Sky Sapphire in the Bracers)
- +22 Armor
- +1 Defense
- +21 Dodge
- +36 Hit
- -2 Str
- -26 Parry
Mimirons clearly win in every aspect.
Mark of Unyielding vs.
Shard:
- +6 Sta
- +6 Dodge
- +42 Hit
- -18 Str
- -336 Armor
Toughest decision. Mark is really really nice and the 336 Armor could be better than the little Dodge and massive Hit.
I love the Ulduar pieces and am wearing them in all my MT Sets. Running around with more than 200 Hit is just so much easier. If you miss a taunt on Thorim or Transition on Steelbreaker Last, these pieces alone
could have made up for it.
In Naxx this wasn't a problem, on Ulduar Hard Modes it
can be!
I think that these pieces cost you less overall Stats than pieces on other item slots like Girdle (BoE vs. Emblems), Gloves (Freya vs. Emblems), Boots (BoE vs. Ignis) and Shield (Hodir 10 Hard vs. Hodir25). Last but not least, there aren't +Hit items on every slot.