I don't like the guy who sells Catcable so "I" wouldn't buy those.
As far as the difference between silver and copper, it depends...I can show you copper cables that sound more like silver (whatever that means) and I can show you silver that sound more like you think copper should than most copper cables.
Anyway, in your apparent price range I would try Signal cable, Bolder M80's, DIYcable Superlatives, Homegrown Audio, Puresilversound and Outlaw.
One other thing, I have tried SilClear on copper WBT NextGen connectors and made them sound identicle to the Silver NextGen ones. In the future I will only buy the copper ones.
Connectors and how they are connected play a pretty big role in how IC's sound..of course differences in how they sound (or change your systems sound) depends on how revealing your system is.