When the conditions are optimal for the mk21, I find they produce stunning results that cannot be equaled with any card or hyper.
Couldn't agree more with your statement.
On the caps the idea of going for MK41 is enticing me for having a different sound, all together, a dry one as stated by Schoeps sound. My idea is first going to the extremes and then converge to the centre, as you did. Not yet decided, though ....