Just the kind of heavy armour set I've been waiting for. But I think it relies too much on getting hit by enemies to gain a benefit, getting crit 20 times to gain the max effect. I think thats a bit too much.
I suggest something like this:
Warrior's Fury - When you DEAL critical damage, your weapon damage is increased by 28 for 6 seconds. This effect can stack up to 20 times.
This way its more about your own performance that will work with the set rather than how often your enemy crits you, plus it still stacks 20 times so there's a build up time before reaching full potential.
Added benefit of also being useful in PvE along with PvP.