I agree with Arthur. This is a complicated subject and you're going to have to assess your power-quality situation with your ears by auditioning pc's and/or regenerators and listening to judge the sonic changes. In addition, another consideration in deciding about the quality of your power is whether or not you feel you're getting the performance expected from the quality of your gear and system. If the answer right now is "no," then power-quality may play a part in under-performance. For me, based on my gear and system, plus the results others are getting with similar gear, I feel my setup is not playing up to it's potential.
I use a Shunyata Hydra 4 which is fairly well respected as a conditioner and don't feel that my front end gear and system sonics are up to potential. I've tried various changes to my system (electronics, etc.) Wanted to do dedicated lines but that's impractical for me in my current home. So I'm about to try a regenerator to see if that will raise the level of performance in my system. Some good questions to ask yourself are, "am I satisified with the sonics my system is producing? And, does my system seem to be performing up to it's potential or is it underperforming based on my gear?" The answers may help you judge your power situation.