Armor

After the November 2009 change to Armor of Faith (cloth only), the number of options for armor dropped considerably. While Critvengers might end up in heavy armor, it makes no sense for anyone else to bother with armor proficiency, so this is a list of cloth armor only.

Properties

Bloodthread (PHB)

A perfectly good default armor for everyone: +2 bonus to AC and saves while bloodied. Even Martyrs probably want to reduce their rate of getting hit once they've gotten bloodied.

Battle Harness (DA, 4+)

In my experience, the +Init is worth more than the free-action draw, since I don't think of Avengers as having to do much juggling. But the +Init bonuses are valuable and harder to come by than one might think. The only reason I'm downgrading to black is the expense: 4+

Robe of Eyes (AV)

I've had plenty of success hitting things while blind just from rolling twice. But if you successfully kill it while blind, you need to get unblinded to oath the next thing. This robe will help. It also gives you a boost to your best skill, freeing up your head slot. I'm not a huge fan for two reasons: (1) Blind isn't all THAT common, so it's a wasted property in 95% of combats. (2) I can't get over the visuals.

Sanguine Vestments (AV2,3)

Nice conditional bonus to AC as a property for MODs. Makes the Devas similar racial property a big enough difference matter. Without it though, +1 doesn't change the math enough to change anyone's tactics unless you've already made a substantial investment in AC.

Shadowflow Armor (PHB,Rare)

Bonus to Stealth checks, and not too expensive (+2). The Character Builder and Compendium have it as an Unnamed bonus, and that's great... but PHB has it as an item bonus. Note that you need Total Concealment to stealth, so the encounter power won't let you hide in plain sight. But it will let you move into plain sight without dropping stealth. And then at Epic, it's just Invisibility, so that works.

Sylvan Armor (PHB)

Item bonus to Stealth & Athletics. Shadowflow Armor is better if you can find it.

Utility

Armor of Night (AV)

The property is Resist Radiant, which is almost completely irrelevant. The encounter power gives you immunity to OAs, which can help in positioning. High-priced though (+3)

Counterstrike Armor (AV2,10)

Very expensive to do 9 or 18 points of damage to someone. Just the first means it won't make anyone run, unless they know about it (and they don't). And by level 30, 18 damage once an encounter is just sad.

Desperate Resolve Vestments (PHB2)

Insubstantial for a turn as an II is always good, spending a healing surge is gravy, and it's not horribly expensive (+2). But the cheapest one is +3, and it's basically obsoleted by Ghostphase Armor in Epic.

Displacer Armor (AV)

One round of "roll twice to hit me". Killed by the update, return to vendor for a refund.

Enduring Spirit Vestments (PHB2)

The fact that it's got a trigger is almost irrelevant, you've got good enough Channel Divinity powers that you're sure to use one in any given battle. And it's an encounter long AC buff. So that doesn't suck for a daily power. Cheap too (+1).

Flowform Armor (PHB3,4)

Being controlled sucks, free encounter saves rock. For Critfishers that have the AC of an unattended object, this is great... But the majority of Avengers actually have a pretty good AC, and should have some of the better defenses overall, and so should find something else.

Ghostphase Armor (PHB)

Necrotic resistance is one of the 3 that seems to ever matter. But the point here is the daily power: insubstantial (good for Martyrs) + Phasing (good for anyone) for two turns. It is expensive though (+3), and the phasing doesn't show up until Epic. Prefer Desperate Resolve Vestments until then.

Illithid Robes (AV)

Psychic resistance isn't great, but isn't pointless. "Once a day, don't go unconscious" is pretty good if you've drawn too much aggro, but I don't know if it's good enough to justify the price (+4)

Radiant Temple Uniform Armor (AV2)

A constant +2 item bonus to stealth, so it's decent at low level, but tails off in utility as you level. But the power is an encounter power, and you've plenty of nice effects that shift you. So that part's great...

Repulsion Armor (AV)

One encounter, push away a person a round. Not quite Divine Rage "I'd like Oath now, kthx", but close. And cheap (+1).

Robe of Contingency (AV)

The flavor may be about running away, but the power says nothing of the sort. And being able to spend a healing surge also isn't shabby. Kinda pricey though (+3), especially since the power is an immediate reaction, not interrupt.

Robe of Scintillation (AV)

Because it can't benefit from Expertise, the daily power won't keep up with your other attacks. But it's cheap, and the power is a useful control attack.

Robe of Stars (AV)

Most DMs should see this as a prohibitively expensive Rattlesnake power, and give you a free round. They may run (Chasers). Other DMs will just suck it up, in which Martyrs will like running around blinding people while powering up.

Stoneskin Armor (AV)

5*Tier Temp HP as an encounter power... not bad. Not cheap though.

Sunleaf Armor (PHB)

The draw is that you have a large Dexterity modifier, and this gives you a strike-back ability. The problem is that it's a weak daily power, and since it's a daily can't really be used as a rattlesnake power (so enemies won't avoid hitting you in fear)

Temporal Armor (PHB3,20)

Prevents you from using an action point, for an inferior effect. And is just silly expensive. Buy the +2 Symbol of Victory already.

Armor you buy for others

You know that joke about the best armor for a wizard? (Plate, you put it on the fighter). Kinda like that.

Legendmaker Armor (PHB2)

For the bard. Get an extra standard action when you just nuked your oath target.