Hi aolmrd1241,
I think there's been an abundance of common sense provided on this thread based on actual listeners experience with their systems.
The point that's been made repeatedly is , simply try and hear for yourself. The beauty of these fuses is the simplicity of their use. Pop one in, take it out and compare with another. Listen for a while in one direction, reverse direction and listen again, very easy to do. Afterwards determine if you did or didn't notice/hear a difference. Results may not be uniform amongst all listeners.
All I can report is what I hear with various fuses in my components. They go well beyond subtle but fall short of "jaw dropping to the floor". I relate to Oregonpapa's written comments because my listening impressions are nearly identical to his. This is as easy as rolling various tubes, yet the potential change (of fuses) is greater in some cases.
Compared to cables and many audio products the premium fuses are inexpensive yet yield very noticeable improvements. This has been my experience and I'm very happy to have them. No doubt YMMV.
Charles,