+10/20 Physical Armor Bonus Questions

If I have 4 pieces of +10 physical wvyern armor, do I get +40 physical total or just +10 physical? If it is 4 pieces of gladiators, is it +20 or +80 bonus?

I ask this question b/c a lot of IWAY warriors seems to prefer gladiators armor that gives +20 physical attack. Yet, most damages are usually elemental or armor piercing(orders, obsidian flame). Why the strong preference?

4 pieces of +10physical armor means that on those pieces with a base AL of 80 you will have an AL of 90 vs physical while 80 vs elemental dmg. This is a consequence of the chance of a hit connecting to a certain part of your toon (head, body, arms, legs, feet)

And they use gladiators because it is hands down the best armour statistically seen due to the extra energy. Heck full knights is useless anyway seeing that the absorption mod is global in stead of local which imho blows...

You misunderstand, the damage you take depends on where you get hit. There is a % chance for an attack (non-spell) to hit your arm piece, legs, chest etc. Therefore each (Gladiator's Amor) has 80 armor and an additional +20 against physical attacks.

As to why its prefered, I really cant think of a better warrior armor. The energy and defense is probably the best.

Edit: Renegade beat me to it.

The only 2 armor mods that are global are the "Reduces damage from attacks" on Knight's and Ascalon Armor, and the +15AL while casting on one Mesmer armor. Both of these do not stack with multiple pieces.