I also favor defense over assault on accessories on all of my Himes. Everything Slashley said is correct and I'll add one more thing to the list in favor of defense over assault- Assault/Vigoras triple weapons. After full assault and maxed grid and himes, the only true way to add more damage is through vigoras weapons. Those require you to maintain high levels of hitpoints and sustain for their damage to apply. This makes every bit of damage reduction/heal and defense valuable. (If you go for the assault/pride weapons instead, this isn't a plus for defense over assault.)
Dejnov.