So I had my Horus reterminated to 4.4, and I actually like it a lot with the Phantom from the balanced output now. The balanced output of the my (modded) Sony is a bit warmer than the single end, so the combination works wonderfully by adding a bit of clarity without becoming bright. I think I will leave the pairing for a while. It was the same on the RW AK380cu, where I preferred it from the balanced output, which is a bit warmer than the single end. So if you are using the WM1Z as main source, I can understand why you liked Horus, as it brings a touch of clarity to the Sony's warmer tone.
As for some brief impressions of the new cable, the thing that striked me most is that this is a new type of sound altogether. Coppers, SPCs, and silvers generally have their own type of signature (although there are of course many variations in their actual sig), and the palladium-plating adds something new. It had a sort of hi-fi sound, but in a cool way. For instance, even though its midrange was slightly warm and bodied, it added a clear and fast sounding treble on top. So not as warm as a regular copper, but also not as clarity-focused as SPC's can be, although the treble itself was detailed. There was a sense of authority in its sound, resulting from it midrange transparency, along with its body. By comparison, Horus sounds a bit leaner and brighter. In addition, its bass offered greater extension, resulting in a powerful sense of impact. I didn't compare or listen enough to get a sense of the quantity of its bass, but it didn't seem lacking or overbearing. There was also another prototype, where the treble was a bit more prominent, resulting in wider but flatter stage. However, I think the majority there preferred the aforementioned one.
Finally, the cable isn't 'just' palladium-plated; they actually played around with some extra materials to refine the sound. It is also a hybrid configuration, but I will leave it to EA to reveal the final details. I also just kinda forgot tbh since it was pretty complicated hehe.
Here are some crappy smartphone pics that do not do it justice, it looked pretty badass.