Well Chris, there you have it. Somewhere in this excellent group of candidates IS a "best" for you and your system.
I did want to point out however, that "system synergy" is not entirely a hit and miss affair. Yes, try out cables until you close in on the ones that sound 'right' to you. But remember, you have already "unchosen" certain (very otherwise qualified) candidates by your prior selection of other elements -- Koetsu and ARC, to name two. And I was kind of wondering what cables and/or other equipment attended those decisions -- don't get me wrong, I don't disapprove of them; just curious.
As to your second question, which seems to have gotten lost here: After many years of combining and listening to various high-end (and OK, expensive!) cables, I have come to the conclusion that using all the same make (and model) cabling whenever/wherever possible in a system adds more to system synergy than any mixture of makes/models; no matter how well combined or optimized. I know others will disagree with this position, and it's only true when using premium products as suggested by everyone here, but I did the "mix/combine/tune your system" cable approach and finally saw the light This was driven home to me when I purchased my Venustas phono set at CES from Jim Aud, the owner of Purist. He insisted (practically to the point of giving them to me for free!) that I take an additional pair of RCA/RCA Venustas to go from my Levinson 25S phono pre to my Levinson 26S preamp. I have repeated this exercise in my own and other peoples' systems enough times now to know it works. I'm pissed off that I can't explain the 'science' of why it works, but I know a scientific reason exists and eventually, I'll get to the bottom of it ;-)
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