@bwguy A few months ago, I did a bit of a power cable shootout including the following:
Synergistic Research Atmosphere UEF Level III (not HC)
Synergistic Research Atmosphere X Euphoria (not HC)
Synergistic Research Galileo SX
Shunyata Sigma NR (version 1)
DH Labs Corona AC
I would say of all of those, the Shunyata and the DH Labs AC cables were the "hottest" sounding. The two were almost indistinguishable, and I preferred the DH Labs, which was a bit less fatiguing. This is saying a lot for DH Labs since 1.5M of the Corona is $950 whereas the Shunyata Sigma NR retailed for $2500+.
The Synergistic Research cables I found to be less bright, less fatiguing, but also allowed for more to come out of the music overall. My ears heard more while trying less hard, if that makes sense. The Atmosphere Level III is a great cable on the used market as they pop up around $1K - $1.2K, but they are not the end game on slam/current delivery. The Euphoria is just a bit better, and Galileo SX is what I consider to be my endgame reference.
I would say that it also becomes system dependent. I’ve tried Galileo SX in some places, and the sound is just too beefy. Likewise, I’ve tried the DH Labs Corona and Shunyata cables in places that needed some zip and slam and these cables can also do wonders if the synergy calls for it.
I guess that at the end of the day, in a cost-no-object situation, I prefer SR cables. I find them to deliver more, but I don’t find them to be fatiguing in any way. I’m not sure "lively" is the right way to describe them, but they have done wonders in my system. I also really love the DH Labs Corona for what it can deliver in its price point. I still haven’t found a cable 3X its price that I like better.
Disclaimer: I am a DH Labs dealer, but hopefully you can sense my honesty in this post.