Yeah, it has been some years and I don't remember the details but my ZSTYX certainly benefited from breakin even though they were only a few feet long.

That’s interesting. That two systems can respond so differently.

We sourced the same cable from the same place, but mine were not dark at all. Swapping from the ZWire braided OCC copper cables, the ZStyx 8 gauge wire was more clear, detailed and airy on the top end. The midrange was more open and tonally pleasing. The bass was a bit less punchy at first and a let down, but seems to have become more punchy and impactful over the course of the weekend. I had a very enjoyable listening session last night. I feel like there is more transparency overall. With my Omega SAMs, they do not sound overly bright at all. In fact, the touch of clarity on the top end is what I really like about the ZStyx. I’ve had them in for several days now and in my system, I am preferring the new cables. I used pure copper connectors with gold plating, bananas on the amp side and spades on the speakers. Seems to work well for me.

Hopefully yours will open up more in the coming days.