I should have mentioned this before but one of the reasons that I though 2 runs of cable may be better is that a y splitter may not be enough. On your amps, you need to see how far apart the left and right inputs are. Sometimes they are right next to each other, but often they are far apart. If they are too far apart you'll probably have to have something custom made. Unless BAT says otherwise, I feel 2 seperate runs would be much better.
As far as what cable you should go with, the options are endless; as are the opinions. If you don't mind going with used and want to save some money, Audioquest makes a cable called the Jaguar. Its discontunied but is almost identical to the model that replaced it; the Columbia. I own both. They sound so similiar that I don't think I can tell the difference. People are always so quick to upgrade without much thought, you can sometimes get great deals on older models that are just at good as current. Also, copper AQ is known, not only for sounding good, but works with just about anything. Its a really safe bet. Also, you mentioned Purist. The Cable Company lent me a pair to try (Aquasomething, and they were about $1000-1100), and I thought the AQ was a lot better. Please remember, though, thats was just my opinion. No question that others will feel different based on what they like.
