I'm running 5 units, all currently with identical settings. It's a mixed bag on performance.  The temps are all very close, but the hash rate varies amongst the units from ~4000 to ~4450.  I was hoping for a bit more consistency but this may normal.  I'v also got one unit where ASIC#1 is totally DOA from Spondoolies-Tech.  Not really sure what to do about that.