I run a bi-amp system with 8tc but did not in fact by them for the pretty colours. True, I bought them at dealer cost which always tends to sway a bit but the research that I had done on this cable at the time(almost 10 years ago) had shown alot of favor to this particular wire. Having had a chance to listen to it on the same speakers as I had and similar amplification, this cable had a very transparent and very musical quality to it, something that is not for everyone but personally what I was after for my system at that time.
There is a shitload of cable on the market and it's the same old thing, trust your ears. Hopefully you can find someone who can lend you a few pairs that you can demo and make your mind up as to what works best in your system.