regarding the hit or miss thing...compared to my experiences with hearing aids for someone to like the cis I think it depends on how resistant to change they are, how open-minded and stubborn to get through the "breaking in phase"
for example I had to identify the "noise" that I haven't heard for the first time or have forgotten that sound the other night when I was thinking there was something wrong with my hearing aid some strange echo sound or feedback...it was a floor heater running in the other room!!! I was relieved to turn that thing off and know now to ignore that sound...
