XLR & RCA caps

Agree with the above. I have used the Cardas RCA and XLR caps for years, (ever since they have been available).

Agree as well. I use Cardas rca and xlr caps. Can't say I hear a difference but like the fact that dust does not get in these openings of my pre and cdp. This is a tweak to buy when you are in the mood to tweak, don't want to spend alot or be disappointed if the tweak does not improve your sound.

I have the cardas caps on rca females on my pre-amps; no change in sound I can detect

Same for me. I have some rubber Neutrik ones I threw in to make up an elecronics order.

That being said, if I could see them from the front, I might go for something expensive.