Dear Toga, as you are lucky enough to have full sets of IC and SC, I believe the ultimate tests is to compare brand against brand, both IC and SC from the same brand being connected at the same time.
I understand you can do a Shunyata versus Transparent versus Kubala Sosna shoot-out.
Because you are very experienced in this hobby, you know that you'll need 30 min to 1 hour "stabilization time' after each IC and SC cable swapping before being able to make a significant judgement about sound quality.
Your findings will be very interesting!
Cheers from France