The M2 bookshelves are absolute keepers. They have no problem performing in my 4200 cu.ft. room. I'm 12 feet away and can push them to 103 dBC peaks without a problem (3 subs included). They can likely go louder but I'm feeding them with the 1500 so I'm holding back for fear of vaporization. I am in awe of the clarity, soundstage and imaging.

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