I have no parses yet to post , till i get them sent to me , this is what i found when testing def on 58 mobs (sphene doblyns)


WAR ifrit's axe
cobalt gear: 644def 96 dmg 282vit (291 avg dmg taken) 3664 hp

AF gear : 586def 292vit (334 avg dmg taken) 3688 hp

058def 96/58=1.66 dmg per def added


PLD no shield
cobalt gear: 656def 292vit (286 avg dmg taken) 3167 hp

AF gear: 604def 278vit (312 avg dmg taken) 2937 hp

PLD with shield
cobalt gear: 695def 292vit (262 avg dmg taken) 3167 hp

cobalt gear: 695def 315vit (248 avg dmg taken) 3190 hp (with a vit+ cobalt winglet.)

tests were done with no jewlry added. I do recomend def materia melded over vit simply because you can add 36 vit on hq rings alone, then you can add vit to legs and the sword , wich leaves only two spots in wich to add def. I recomend to keep the ratio 1 vit for every 2 def. dmg deflected overtime is a MUCH higher payoff over HP materia added. That being said, anytime you anticipate a quick and fairly painless fight, WAR is a better option simply for its ability to add to the dps, but if damage taken or keeping the tank alive for any duration past a 5 minute fight, I would go with a PLD tank as the safest route.