Apopira
I haven't heard Cardas Golden Reference SC in my system so no I can't, but I will say I think they are not as forward sounding as the Purist.
Personally I wouldn't hesitate to use Cardas GR SC as every system I've heard them in I liked their full copper sound without any of that lush/soft silver sparkle, a characteristic I prefer not to have in my system at this time.
Audiofeil
Don't you sell any any 100% copper cables?
To my ears silver still sounds like silver.