So Pete, did you try tham out before you shipped tham? Did you notice any difference in sound due to these connectors?
I have no doubt that there was a difference between stock and these. I am not sure that that difference would be better, or worse, or meaningful in terms of the price though, unless one heard it in their own system. But I am absolutely positive that it would be different.
I can say that from my limited experience with connectors of all types, RCA, AC, IEC, spades, bananas, etc. that connectors are very important in the overall performance of a wire and have a tremendous impact on the sound of that wire. However, "the best" may not necessarily be "the best" in every situation.
The ones Pete uses on his stock cables are one of the few available that is all pure copper. And they are very good indeed!