I've used a few conditioners... The biggest issue with all of them is hum. If you can find one that doesn't hum AND is effective at power conditioning, you've got a winner.
What's bad is that you can have hum at person's house and not another. At my old house, everything hummed... at the new house, only 1 conditioner hums... (of 2 Cyberpower 1500's I use for computers) So at least now I can determine humming vs. non-humming devices.
Rich pointed out that DC offset (I think) for the home voltage may be the culprit for hum. He's borrowing a conditioner of mine but it hums.. I need to hook it up here and see if it hums... Then get the power company to fix the DC offset at his house if that's the problem.
Of the coniditioners I've tried, they all did 'something'. I even made a simple bypass cap to filter noise on a power strip. That works well, especially in noisy environments.
Power Cables are very subjective... It'd be fun to see the heard differences correlated to scientific ones. However, I wouldn't wish that work on anyone. Plus, at the end of the day, I know what sounds good to me, in my system.. and I really don't need to feel validated by numbers. There was a time I was out to prove what I was doing was 'right'. Now anything I do is right because it's what I want to do.
Well, enough rambling for this morning.. time to get to work...
-C