Couple notes:
Over 30 units, batch2-4, they seem stable with the jan 7 firmware. Prior to the Jan 7 firmware, we had them dropping a board randomly cutting hashing power in half.
Consistency is pretty decent, although we have 1 unit with an over 10*C spread between the two boards.

Noise is pretty bad. I was looking to run one at home (for heat) but it's quite loud (as everyone else has observed). Has someone actually enclosed the unit (I believe someone mentioned saran wrap earlier) and recorded any results? I'm just not sure it's worth the hassle of replacing the fans for a few decibels quieter noise, especially for the increased cable mess, etc. I wish the firmware gave the option to set fan speed manually, or target temperature. Even at below 50*C it's quite loud, and doesn't seem to reduce the fan speed that much at all.