I had many Dominus B and C power cords 15+ years ago. Great great midrange lushness, musicality, a fairly good bass foundation, but the upper frequencies, especially with the B, were severely lacking extension and detail. Moving on to Stealth, Dream State and Silent Source power cords brought on so much detail that had been masked by those older Dominus cables.
I have to believe that refinements in the Purist line in the last decade have rendered significant improvements here. I would suggest you contact Albert Porter, a long time user and dealer of Purist cables to have him send you some cables to try in your system and compare with your Dominus cable.
John