I just picked up boots for the Act 2 armor set and sticking a warding rune in it gives me 306 resistance to fire. Placing the same rune in Aveline's armor give me 1,000+ resistance.
Is this working as designed? As I'm using Hawke as a tank, this is hurting me during some battles.
Runes not only scale with the quality of the part you put it in but also the effect depends on where you put it. You get more resistance out of putting it in the chest piece.