I would have expected the 7" Dayton RS drivers to sound very good in an array. I built an MTM using these drivers and it sounds very good. I wonder if your RS8 array doesn't need more bsc for its placement in your room. Some speakers that sound very warm in my smaller upstairs listening room sound a bit bass shy in the much larger downstairs room with hardwood floors, lots of glass, etc.

Like I suggested, you'll probably like many charactristics of a single driver array, but at some point you my find yourself wishing for a tweeter array to make it perfect. Just my two cents based on my hearing the single driver arrays at the RMAF.