About two years ago my main speakers were a pair of B&W CM5's, the third pair of B&W's in a row (I have a Velodyne sub woofer as well). I had the hots to upgrade, listened to the PM1 (which was a step up from the CM5's), but had my heart set on the 805D's...until I was invited to an event opening my eyes to the Totem Element Fire monitors.
I returned to the showroom, stack of CDs in hand on a slow day and spent nearly three hours doing some careful comparisons and ended up ordering a set of Totem Element Fire's.
The Fire's are in a 13.5' x 22' living room, close to the back wall, driven by a 200wpc McIntosh solid state amp (and they sound fantastic). I don't listen to music at ear-splitting levels, but when I'm listening to them loud, the needles on the McIntosh hover around 2 watts. I suspect your MC275 would drive them beautifully!