i what is your opinion for this 2 cables the audioquest castle rock vs the kimber kable 12 tc ?
Only you can make that decision...listen to both and chuck the other
Do you really need your cable to be that thick?
You evidently want good speaker cable.   I have searched for a long time for the perfect cable for my system.  I had Audioquest, Cardas, Kimber, Purist...and the list goes on.  I finally found what I was looking for..... big deep bass, clean highs, big dynamics, wide open soundstage.....If you are seriously looking for an excellent cable.  Call Paul and get a sample...he'll probably not even charge you postage...FREE.   ClearDayCables.  Look them up on the internet...not expensive....and just plain wonderful.   I am not the owner of the company...just a very happy user.
Clear Day Cables all the way. Second Paul is a great guy to deal with.