I have a CAT SL1 Ultimate pre, and I think I know where the fear of silver comes from. The CATs are very revealing, as you know, and often what is revealed is all the high requency hash. Silver cables tend to reveal more of the high frequency stuff too, and so the combination of the two can be a little frightening. Some silver cables are not very well balanced as well, and the problem gets worse. In my system, I use my own cables, which use a blend of metals, including a high proportion of silver, and sound just about right. I also own Siltech SQ 88 and SQ 110-- to my ear, they are one of the best sounding cables around-- not neutral, but really good and definately worth a try. They are a blend of gold and silver. I also like Cardas Golden Reference for a slightly warmer sound. Cardas gets a bad rap sometimes, for sounding mushy or soft, but the trick with their cables is to plug them in and leave them alone, and to let them break in for a good long time. It makes a big difference. If you keep moving them around, you'll never hear their true characteristics. The reason? Each tiny strand of copper that goes into their cable is insulated, so there is quite a bit of dialectric static or charge to discharge. Everytime you move the cable, say, plug in a different cable, you upset the dialectric charge balance (or whatever we call it). Anywy, if you treat the Cadras cables well, they will sound detailed and smooth.
As far as I know, there aren't any electrical issues with CAT and silver cables-- like impedance or capacitance.
Try some Siltech. I think you'll be amazed.
Hope this helps,