The combination of countermeasures and insulators protects me from power based debuffs. Even if that is not enough of a theoretical defense, empirically it works quite well in STFs. I can go 3-4 sorties in a forward, attacking position without a death while escorts wipe regularly.
My guess, though I really don't test, is that it would work reasonably well in PvP where power debuffs are more prevalent.
Reduced ET cooldown, random Borg regen, and parallel heals allow me to absorb much more damage and operate at really low hull percentages while plasma distribution and photon det give me slightly better offensive capabilities with the top of the sundae being that I never have to worry about high yield plasma torps.