I've found the M5/1000-2 combo is bordering on inadequate for my 4200 cu ft space at 14 feet away. The M100/1000-2 is plenty! This is with subs on. The living room at 1p feet away is a different story. The ADA-1000-2 is plenty loud with any speaker.

You really can't judge anything from the capacitance figure. You have to know the dynamic power the amp is spec'd for. Axiom specs that figure. Most others do not.

House of the Rising Sone
Out in the mid or far field
Dedicated mid-woofers are over-rated