I have some Musicable for speakers, from Germany-- claimed (I say claimed because I have never even tried to verify it) to be made of pure silver. It sounds good. In my system, perhaps a tad bright, but definitely good. The main thing for speaker cable for me is pure materials, proper weave that works in my room, and no iron or other metals in the single path-- especially in the connectors-- both male and female. Where I’m at is in room correction mode. I’m getting more improvement from adding sound absorption and dampening here and there than I think I’m going to get from upgrading components at this point-- and I’ve been doing this for a very long time now. You may be at a point where you know your system inside and out, have a great room that’s not messing things up too much, and are going for the harder to get improvements.
It does not surprise me that you have found a cable that costs way less than another that sounds better that its more expensive peer. It may be that in your system, silver wire gives the sound the character that you prefer.
In the end, your ears alone are the judge. Better, or not.
I just know from long experience that more money does not equal better sound, and that there are many other factors that are at least as important.
I have an acquaintance that has spent a fortune on his system-- way into the six figures-- but his room sucks, his setup is wrong, and it’s just plain sad about all that money and gear adding up to a very mediocre sound. But try telling him that and you’ll hear a long rant about what this costs and what that costs. That’s confirmation bias on steroids!