Armor as Damage Reduction Varient rule clarification

[ITSHAIRTIME]

Ok im starting a pathfinder Campaign with the alternate rule for armor as damage reduction just wondering what changes to damage reduction and what stays defense? for example a shields ac goes into defense but an armors ac goes into damage reduction aswell as natrual armor and can be bypassed by magic. but what about things that dont list a specific type of ac bonus like mage armor gives you +4 bonus to armor class does that go to defense or damage reduction? sources would be much appreciated.

[Jeraa]

Mage Armor does have a specific type. It is a +4 armor bonus to AC. As such, it should grant damage reduction. (Armor bonuses are not added to defense, so the only other option is damage reduction.)

As far as I know, there is nothing that adds an untyped bonus to armor class. They all have a specific type.

[Aristin76]

Becareful when your players realize that adamantine weapons are far greater in this ruleset. Adamantine anything really. I enjoyed the lower levels using this ruleset, but after 7th level it lost a lot of luster and became a chore to prepare encounters. At 4th level it started to foreshadow the issues at hand. Best of luck to you using them. I love the concept of DR provided by armor but have yet found a successful way to incorporate it into PF.