I think what is interesting to note here Misfit is not about mental break-in at all, but perhaps something more obvious, that the sound of the M2 is different enough from the M60 for you to hear that difference.

Listen to the 2 speakers again in a month, side by side, and see if you can still pick out the sound differences in the high end, or otherwise.

"Those who preach the myths of audio are ignorant of truth."