Better XLR/RCA adapters

The Cardas adaptors are on sale now from Partsconnexion and at $90, while more expensive than the (similar) $4 model from Parts Express, the Cardas version would probably pass the "audiophile approved" test without spending $500, which just seems to be a silly price for something that will likely be plugged into a typical Neutrik connector or similar.  The SMc adaptors discussed by tvad below would also be a good choice as I believe they were made to work with Steve McCormack's $20K VRE-1c preamp.

@inna 

mitch2, there are also Cardas adapters for $150 pair. Is there real difference?

I couldn't really say that it would be worth it particularly when you consider most equipment manufacturers, even those selling high dollar gear, use basic Neutrik XLR connectors and something similar to Cardas RCA connectors, although some do use more expensive connectors by WBT and others.  I would probably try to stick with adaptors that do not include a short cable component, just to keep things simple and to allow my main cables to be the primary conduit.  If I needed adaptors for a temporary situation, I would purchase one of the less expensive options from Parts Express.  If I needed them long-term, I would be very comfortable using Cardas adaptors, or the SMc Audio adaptors discussed by tvad, but I couldn't say for sure that I would hear a difference between those and the others.