Infraction: 6. Do not post unless you have something new and worthwhile to say.
Message to User:
This has been answered several times. Please search and read before posting. Thanks.
Well, 10% armor penetration is roughly 2.5% damage on a boss while in pvp it varies much.
Atm PTR arp was buggy, so I hope we can test this out and understand how they think to make ratings, debuffs and buffs stack.
Here's a question
Are the various armor pen's additive or multiplicative? One of the problems with armor penetration was it was devalued the way it stacks with sunder, with everything being percentage based that may change.
Your looking at 30% in Battle stance with sunders up, 45% if you are mace spec, there are proc based trinkets from uldar that give another ~35%, with minimal gear we're getting into the range where armor pen used to have its value greatly inflated.