Thoughts on Armor as Damage Reduction

[OmegaZ]

I'm going to be starting up a new Pathfinder game (Way of the Wicked: Knot of Thorns by Fire Mountain Games) and I'm considering using the armor as DR rules from Ultimate Combat. Does anyone have any experience with these alternate rules? The way critical hits work confuses me a little bit, but I can always drop those out.

My biggest concern is the fact that these are newbies to Pathfinder. They've been playing 3.5 for awhile now, so it won't be that big of a switch, but I'm worried that changing this on them too might be a bit much.

Thoughts? Advice? Words of caution/wisdom?

[wraithstrike]

I would not use the optional rules until they got used to all the regular 3.5 to PF switches.

[Helaman]

I use armour as DR - 1 for light, 2 for medium and 3 for heavy but then again I also use armour damage rules and all sorts of other rules.

All that said? I'd follow wraithstrike's advice and get them playing vanilla PF for a while first.