We've come full circle to what Danny said: "So maybe I can figure out a passive woofer solution for the 8" and 10" coaxial models with 12" servo subs for the 12" coaxial model."
It appears as though he's talking about two models, one of which the 8" and 10" Radian woofers don't currently exist, and the other that is readily available -- the 12" servo subs with a 12" coaxial (the new Super V???).
And yes, JJ -- for a party speaker, you absolutely want "stadium filling" sound, even in a medium sized room, so a 12" coaxial speaker with servo subs is the way to go if price isn't a consideration. However, to prevent from overpowering the room, the subs ought to be open baffle.
This project screams of needing a modular approach...