Should not, this would add another 7k of ac (or at minimum 5% more dr till common 6.5% dr, that would be insane for a so easy to obtain set bonus and you won't willing to drop this set until t7 or t8 with 1401 armor more on it :/). 1.4k finally ac looks more like something regular for me, since no other set bonus provide such a huge jump and adding another ~ 1.0-1.5% dr should be more than enough as a bonus.

Armor / (Armor/100+(58.8+(Level-60)*4.675)) ->
16k
16000/(160+105,55)=60.25% DR
18k
63.04% DR
20k
65.46% DR
22k
67,58% DR
24k
69,45% DR
26k
71,13% DR
28k
72,62% DR
30k
73,97% DR
31665
75% DR

As mentioned above, it's at least about 1.5% dr. Not that bad at all. And blizzard can't make 16 sets of t4 per class, one for pve tank, one for pvp tank/dps, one for pve dps cat, one for pve dps oomkin, one for ht and one for hot healers..

Ofc, adding spirit and int may annoy a pure pve tank, but it's important for shift out, regrowth, rejuv, shift back - else you may lack the mana to even shift back.. Wouldn't that annoy you as a casual pvp player? You may drop the point that they could take the Gladiator stuff, but those lack 1-2 stats in total while adding resilience.
You allready get 2 different set boni, depends on your form. Thats quite nice, and 6 slots of gems + metagem where you can put in what you prefer. Thank the designer they only made 2 pc lack of gemslots and not all 5 ending you up with

Breastplate of Malorne
Binds when picked up
Chest Leather
383 Armor
+34 Strength
+33 Agility
+24 Stamina
+19 Intellect
+16 Spirit
Gemslots: 0

or something like that

The earthwarden adds a bonus of 2.2kish extra armour - would you be willing to use Terestians over Earthwarden in most situations, as you deem 1.5k more armour "no benefit whatsoever"? (I have actually been considering this, as it's 2.5% dodge and another 42 stamina, but decided against it because the armour is another 2-3% straight damage reduction which imo is better than the dodge, and I have plenty of stamina from other items). I'm still amazed you would consider not using 4 pieces if it gave 7k armour - that's the equivalent of 6-7% pure reduction. Even if you lost 5% from other pieces because they're worse individually, that's a net gain still, and it's static rather than avoidance based, as well as gaining stats for doing dps/healing if you're required to be an OT in fights (maulgar, hydross, karathress, morogrim, magtheridon to name a few I OT in).

Improved Devotion aura is also 1350 extra armour and I can certainly tell the difference with and without it.

I'm currently using the Helm/Shoulders and planning on getting both chest (+3x12stam gems) and legs in the future as although the legs aren't amazing, the 4 set is rather good imo and I'd never consider the gloves. I got the glove item one kara run because the priest had better and the warrior already had them and ended up getting the healing gloves because the feral ones are worthless imo. I'm not planning on picking up the legs until after I get the chest regardless, as I believe it's a slight downgrade individually from the heavy clefthoof so I wouldn't use them.

Dont get me wrong, I like the t4 set. It's great for hybrid\dps which suits me fine because I like that playstyle (although it's of questionable value in a raid setup). It's just that for pure tanking there are better options available for every slot. Even factoring in an extra 7k AC from 4 pieces I'm not sure it would be the best option considering the wasted stat points, although looking at those figures perhaps it would be by a small margin. Anycase, seeing as it's only an extra 1.5k armor added I really have to question whether I'd ever use t4 for tanking or even offtanking any boss that deals physical damage, so personally I wouldnt want to socket\enchant it with tanking stats but rather hybrid stats as that's clearly what the set is geared towards.

I'm not saying I dont value armour as a tanking stat, quite the contrary in fact. It's just I dont see the point in a set bonus that adds armour to a set that surely isnt intended for tanking. Tbqh though we're only just starting SC and Magth so perhaps there's some raid content out there that will prove otherwise.

Tanking is all about gear compromises. You're simply not going to find an item with Armor, Str, Agi, Sta, AP, Crit, Dodge, Defense, Resilience and a socket, in fact you're lucky if you find an item with 5 of those things.

Malorne (except gloves) does a very good job of providing Armor, Str, Agi, Sta, and sockets, the set bonus to me is just icing. More rage means more threat. And even taking the highest armor items (non t5) for those 4 slots, if it is just 1.4k, you still end up with 190 more armor in Bearform using Malorne (not counting armor from agility) Also quite a bit more Agility than those top 4 armor items and provides 7 sockets that can be used for more sta, agility, or defense.

And honestly, how can you say the extra (if it really is) 7.7k armor wouldn't be worth it, you do tank don't you? +7.7K armor from that set bonus on already high armor items means I wouldn't even have to think about other old and worthless items like MoT or ShotM and could finally just switch to Alchemist Stone/Compass (or Pocketwatch, or Figurine, or Shard ... ) Umberhowl's? Gone. Manimals? Gone I'd even start thinking about replacing Earthwarden with something that had Stamina (Gladiators for instance, since it has Resilience to make up for losing Defense) The Possibilities ...

Squiffy - Because gear is relative and they probably use different "base" stats for the druid. I remember Emmerald mentioning that he doesn't us SotF and some other talents in his calculations, I'm not even sure Emmerald has updated with the changes to Armor/Sta in patch 2.0.5, I believe Skytor uses SotF, Kings, as well as a different (higher) base for his model. And damn you Skytor for making me sign up for google spreadsheets.

I have to admit I am a bit surprised to see everyone mentioning earthwarden here as there tanking staff, I thought feral staff of lashing was considered to be better? At least I've been using it non stop since I got it, and never missed earthwarden.

http://www.wowhead.com/?item=29359
Feral Staff of Lashing
Binds when picked up
Unique
Two-Hand Staff
133 - 257 Damage Speed 3.00
(65.2 damage per second)
300 Armor
+35 Strength
+29 Agility
+33 Stamina
Durability 120 / 120
Requires Level 70
Equip: Increases attack power by 525 in Cat, Bear, Dire Bear, and Moonkin forms only.

Waiting for Wildfury Greatstaff personally - can't get heroic botanica going and the drop chance is so low that even if I could I probably wouldn't see it. Done heroic bot twice just to see what it's like / someone else wanted someone, since then everyone wants to do the trial of the naaru heroics, or easy ones (coilfang/mechanaar) for badges. Otherwise, yes, I'd gladly use it over Earthwarden.

Been trying to get lashing, for the relatively simple reason that picking up the gladiators dragonhide helmet pushed me so far into crit immunity that the defence doesnt matter anymore - but must admit that I am somewhat dubious about giving up any feral weaponskill..

Another noob question, I'm new to the whole tanking idea and looking to get into it.

Can anyone tell me how much +defense you need to be crit immune? And how much defense can I take away if I add resilience instead?

Whilst right on Armor, Str, Agi and Sockets... The stamina is rather low on Malorne. this more than anything else is what disappoints me about the set. Pieces with 36str, 24 stam do not feel "tanking" to me.. Reverse the figures (although truly it should then be more like 24str, 50ish stam) and it would be spot on. Letting you make up for the defense in other slots/with gems. But to be truly good tank gear, yes it must have str, but not as the primary stat above all else. Give me Agi/Stam/AC primary, then +hit and Str as the minor stats.

Here's my deal:

With a Heavy Clefthoof Vest and a Gilded Thorium Cloak, I can get +159 rating, 12373hp, 21674 armor unbuffed. Without, I wear a Ghoul Skin Tunic and a Thoriumweave Cloak which gives me a +110 rating, 12153hp, 22810 armor unbuffed. I do have 3/3 SotF.

So my questions are which items do I want to wear and when? And what gems, if I end up wearing the vest, would be the most appropriate - +stam, +agi, or +def? I can swap out the Thoriumweave and get two dawnstones and a talasite for the vest to compensate - with the empty vest and Thoriumweave, I have +138 rating, 12499hp, 21952 armor unbuffed - but I also don't want to gimp my HP and/or armor rating chasing the almighty uncrittable spec.