disrupt field is better, it drops their defense by a significant amount. powerless/confused means, the player/npc cant use any specials. this is pretty good but hell, they can still attack you. but if you debuff their defense, it means its easier for YOU to hit THEM which is the whole point. the only thing that really matters is who dies first. cuz if you die first, well, you lose, right? =D
in cr2 you need to have very good offense, or defense.. at least one of the two.
my farming loadout uses disrupt field all the time and it works out great.