Hello Darren,
I have personally compared CMR to MR in a modified Pass Labs XP-25 phono stage and modified Merlin VSM speakers. The main technical difference between CMR and MR is the use of a copper litz lattice end cap in place of tin-zinc end spray. AFAIK, this is an industry first for a metalized polypropylene film capacitor. Tin-zinc oxidizes during the spray deposition process, producing grain boudaries with variable impedances across the conductive surface that joins the metalized film layers. To my ears, as compared to MR, CMR has more faithful pitch and timbre, reduced slurring across the frequency range, and a quieter background. Hope this helps.
Regards,
Dave
ClarityCap OEM Sales