Ok, math time.
Bonereaver's Edge: 206 - 310 Damage, let's ignore the 1% crit for now
Ashkandi: 229 - 344 Damage + 21.5 damage from 86 AP = 250.5 - 365.5 damage
For now, Ashkandi leads with 44 - 55 damage. Let's look at the proc damage increase effect. One charge gives you 700 armor penetration, so let's look at having only one charge up. Obviously the lower the armor of the target already is, the more damage you gain, but let's look at some numbers.
- Against plate pvper with usually at most 5k armor: 47.6% -> 43.8% damage reduction. So you get ~3.8% damage increase.
- Against ~2k armor you get: 26.6% -> 19.1% damage reduction. So 7.5% damage increase.
- Against 1200 armor, you get: 17.9% -> 9.8% damage reduction. So 8.1% damage increase.
What's your typical damage with only Battle Shout? Let's say you have 1100 AP with it, so it increases your weapon damage by 1100/14*3.4 = 267. So your damage will be 473 - 577, with average damage being 525. So your damage values will look like this:
- Against 5k armor: 275 without charge up -> 295 damage with 1 charge up. So you gain 20 damage.
- Against 2k armor: 385 without charge up -> 424 damage with 1 charge up. So you gain 39 damage.
- Against 1.2k armor: 431 without charge up -> 473 damage with 1 charge up. So you gain 42 damage.
On average, 1% crit will increase your damage by 1.2% (since 1 in a hundred additional hits will do 120% extra damage). 525 * 0.012 = 6.3 damage. So real values will be:
- 5k armor: 26 more damage.
- 2k armor: 45 more damage.
- 1.2k armor: 48 more damage.
So unless you're fighting a plate user or a hunter, BRE is better than Ashkandi with just a single charge. Not being able to get more than 1 charge up typically means you are fighting a class with lower armor that is trying to kite you and avoid being hit by you. And for those classes, BRE is better.
Against plate you will typically be able to land many hits and thus get more charges up. Let's see how much 2 charges would help against 5k armor.
- Against 5k armor: 47.6% -> 39.6% damage reduction. So your 525 damage goes from 275 damage without a charge up to 317 damage with 2 charges up. Which is 42 flat damage increase plus the 6 damage on average from having 1% crit on BRE. So total of 48 damage increase. Beats Ashkandi.
With 3 charges up, Ashkandi just can't even compare.
And I forgot to add that the 1% crit gives increase to Execute damage, since it only scales with amount of rage you have and your crit chance.