The chief advantage of Pacters is that they get a large supply of on-demand minions who are unflinchingly loyal and capable of doing most things that humans can do- minions that are completely disposable, since conventionally-summoned Shadows don't care if they're destroyed, and you can just call them back with another spell.
Even a mook-grade henchman is dangerous because you can hand him a combat rifle and tell him to spray and pray for substantial damage. If the opposition you're facing is so powerful that they can safely ignore a burst-firing laser rifle that does 1d10+2/+3 to hit on top of the Shadow's base attack bonus, then you're fighting something far beyond any normal human soldier. Stick 'em in their face, prevent them from using two-handed ranged weapons, maybe force some Disarm maneuvers on them, put some Shock in while you're at it... and if they die, well, that's a pity- use another spell slot and call them back.
