Thanks all for the input.
My main problem has been in matching a sub to monitors in a room with resonance issues, lots of wood, high wood ceilings and wood floors.... not much sound damping. I chose the Aerial 5b because it is an acoustic suspension and not ported. Bass reflex ported monitors add secondary bass output which is magnified by a lively room and the sound becomes confused, adding a sub makes things worse. I got a loaner HGS10 which was enough to convince me that the flexibility added by the Velodyne dd10 would work. In my room the 5b's are flat to 50hz as tested by the Velodyne set up sweep tone. The sub just needed to be adjusted to do the absolute minimum. The result for my taste and this room is very successful. The down side of this monitor/sub set up is that it is fairly expensive. The upside is that you can get balanced sound without floorstanders or monitors set 4 or 5 feet into the room.