I picked up a used one a couple months ago. Went on the EE fourm and picked up the flava of the day tubes, and am switching back and forth with an IRD purist. Both do different things well. Maybe modded would push it over the top.
Preliminary reports:
IRD: quieter, blacker background, more depth to the sound stage
minimax: more dynamic, fuller, both especially at lower volumes
With the IRD, I feel like I'm back further, with great stage depth, The MM, I't feels like I'm in the 1st or 2nd row, with the sound stage in front of the speakers.
I prefer the deep soundstage.
Maybe with more time on the tubes, only about 20 hours, different tubes, or modded, the MM could improve in this aspect.
You can really tune this pre with tube rolling, different tubes make a drastic difference.
I can't compare to other tubed pre's, this is my first.
Tubes: tungsol 6X4WA, RCA 12BH7A, brimar 13D5
Ryan