Khrys -- I haven't found a used Dominus spkr cable at a price I can afford either, so I'm using Venustas. I think any of my top three choices are flat neutral products, and will provide the resolution your system can generate without coloration. So, for instance, I could understand a statement like "tubes prefer Purist" but not "Purist prefers tubes";--)
I haven't heard the dart amp, but like my ML 23.5 and a couple of other SS amps, I'm sure it breaks out of the typical SS mold in terms of smoothness but without the euphonic warmth most tube amps exhibit. I'm not going to get into the tube/SS debate here, except to say that the best examples of each can provide "live" sound -- except that with SS, it costs more to get there.
I don't know about Kobala product except they have a lot of fans (but so do Nordost and Kimber) so you'd have to A-B them against one of the top three and decide. Harmonic Tech makes an excellent product, but unlike Siltech and Purist, you'd have to buy their most expensive model, because the number two and three models don't share the magic.
All that said, unless you are able to audition used (i.e. well broken-in) speaker cable, you'll have no idea how much (usually) better they will get, or how long it will take. Even my top three won't sound that great out of the box (although way better compared to most ;--) so it's really tough to keep things "apples-to-apples" a factor audiophiles and audio reviewers forget to consider. Basically, unless (any kind of) cable is well used and/or "cooked", I'm not interested in what anybody, including ME, thinks about its performance ;--)
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