@fanotunes, FYI, I started out with the Alpha v1's and then moved up to the Sigma's. I should also mention that in addition, I have a Shunyata Everest that I put in after the upgrade to Sigma. I am very surprised at the comments about the Shunyata's sounding bright. In my setup (REF 6, stock tubes, MSB DAC, Pass 250.8, and Wilson Sabrina X speakers), they were not bright at all. The Everest also made a very noticeable difference in my system, in terms of a blacker background and deeper soundstage. That is why in one system a certain cable might sound mediocre or bright and in another, absolute perfection. Maybe if a tried some Transparents, I would like them better. But because I am perfectly content with my Shunyata's, and the cost of trying to get even better, its not worth it to me.
I found the Shunyatas to be just what I like in my system. However, always keep in mind that synergy between components and room setup are also critical to how things ultimately sound. Also keep in mind that cable changes are often noticeable, but they are subtle, so don't obsess over it too much.