Which way to go for a long interconnect.....

I have used a 15 ft run of Coincident CRT interconnect between my First Sound Preamp and Art Audio amp with good results. The sound was very immediate and musical without any glare. I have since replaced the Coincident ICs with a reterminated 14' pair of Nordost Quattrofil ICs which proved to be a little more laid back, but at the same time more detailed, open and revealing of a sense of space.

I have no experience with Pro Silway, but from what I heard from other people, I have a hunch it will be very open and airy in your system but perhaps a bit "light" and diffuse (unfocused) at the same time.

My experience with AR electronics (a bit dated, I must admit) leads me to believe that you might prefer the warmer, more engaging sound of good copper cables in your system to the more open, airy but "lighter" (sometimes brighter) sound of silver cables. Quattrofil is silver clad copper, and seems to have given me the best of both worlds. Of course the long run of Quattrofil was quite expensive, and I probably would not have gone to had I not already owned the long pair already and only needed to reterminate it from balanced to single ended. It depends on the type of sound you are chasing.

Hope this helps a little. Good luck.
Ron