lloyd - I'll chime in. I don't know the HMS cables. I do know the StraightWire Octave II (now III) which I can recommend. I can speak generally to the subject, having taken a very deep dive over the past couple of years.
I suggest avoiding any cable with out-of-the-ordinary technologies, unless proven to work both with your amp and speakers. I would put Goertz Alpha in that camp. As ribbon conductors they may react erratically with some amps. But Jim used them including for the 3.7 development and he also used Bryston over the long haul - so they are a good bet.
My personal experience is to recommend avoiding any cable using non-insulated stranded construction. Every example of this common technique imparts a wooly haze to the sound. On the flip side, any configuration with coated strands has a high likelihood of goodness. Such cables tend toward expensive. I love Morrow which uses individually insulated conductors, cotton dielectrics, and bonded twisted pairs - all technologies the float to the top of my list.
Now, some exceptions. StraightWire does not individually insulate, rather, they compress the conductor bundle bringing the multiple conductors into close contact along their whole length. Kimber has a multi-gauge conductor strategy which does not individually insulate, but packs them tightly and technically which seems to remove that stranded wire wooly haze. And then there's braid as in Kimber's Black Pearl and Iconoclast's speaker cable (generation 2 is better). The braids use bonded pairs and 'good sounding' insulation materials.
Wire is reactive and variable based on materials and geometry. I suggest paying less attention to the purity of the metal and more to the insulator / dielectric. I like organics best - cotton, jute, etc. Hydrocarbons are suspect to me, even as shrink tubing or exterior jacketing. Teflon (and its family) are clean and clear, especially when un-pigmented. But they're quite expensive. Only one form of polyethylene seems OK to me: XLPE. Most moderately priced wire uses 'bad sounding' hydrocarbon insulators, in my opinion.
Now a story. In this exhaustive cable journey I faced a 'crisis of reference' - too many variables with too many unknowns and interactions - functionally non-analyzable. I contacted Ray Kimber for a chat, citing specifically that magic Black Pearl wire that had been part of Thiel Audio since the early 1980s (with upgrades along the way.) Ray suggested that an impeccable reference would help and I agreed. My working sample is 5' (2' tweeter and 3' woofer) in the SCS4. So he sent me a couple of samples including his Silver Stealth Magneto, and Copper Gyro-Quadratic series, both in virgin clear teflon. They use open braid geometry with the central air core as the optimum dielectric. Magic. I can't afford it for my present Thiel Renaissance vision, but it did its job of establishing a neutral, detailed, problem-free reference. I suggest Kimber to be on your look list. I'm glad to compare notes behind the curtain.
Cable is a wild ride. If anyone tries to make the case that it doesn't matter, ask them to listen. Not only do these differences show up in measurements, they fit with what the physicists know. It's computational feasibility that requires combining causes to reduce effects into a LRC formula that can be easily interpreted. But we hear the issue of the complex causes, not the simplified summaries. Enjoy the ride.
