Elduende,
I have also considered Siltech cables. The fact that there are so many counterfeit cables is definitely a turn off. The only information that I can offer is this.
1. According to Siltech their cables have a seven digit serial number.
2. Siltech claims their rca ends are higher quality.
3. Look for a certificate of authenticity.
4. If you buy from someone make sure you can get your money refunded. You can take pics of the cables and send them to siltech and they will tell you if they are genuine.
5. I would check Spearit Audio or Usedcable and see when they are running siltech's on special.
just my .02 cents.