WotLK lets discuss impurity (unholy talent) for pvp

[guligel]

what do you people think about impurity? is it an awesome must have 5/5 talent? or like i read somewhere its not that good? id like to hear some math

[StefanZM]

Impurity simply is a multiplier for ap coeff. Let's take for example Death Coil. DC damage = 443+(AP * (0.15 * IMPURITY)). Let's take 1000 attack power for simplification ->> 443 +(1000*0.15*IMPURITY) = 443+150 Without any points in impurity. With 5/5 Impurity that would be 443+(1000*(0.15*0.2) = 443 + 180. So 5/5 impurity would be an increase of ~3% of the total damage of DC.

Somebody correct me if I am wrong.