Jack 12's sounded pretty darn good to me, on the same level as the typical concert, and I never went above -10 dB with them (amp setting, so realistically each jack had another 6 dB that wasn't even tapped into. Seeing as we were SUDO outside I believe it is the cleanest sound I've heard out of those speakers although we still had a fair deal of house shake going on even with the sub biased towards away from the windows/house. The only problem I was having was it would have been nice to have 2 subs or most likely 4. It was a tiny crowd/space compared to what you guys talk about (around 30 on dancefloor, while rest were inside drinking 20ft x35 ft carport). I got several compliments on the sound. Apparently I got a lot of people into the music more than usual and I definitely had a lot of fun.
EQ/Proc
Jack's HP'ed at 80, EQ inverting the response curve as much as possible given the DCX 2496, I was able to get 5 stable bands of EQ for each jack, never shut it down once even at 20% free memory.
T60 HP'ed at 26 Hz 48 dB L/R LP at 100 Hz I think (I know overlap is bad usually but it sounded a little better that way than "matching crossovers")
The Bass was intense within about 5 feet of the sub and then became less awesome the farther you go out (no distortion of course so 2x distance = -6 dB) I also think that it may have been better instead of pointing the sub up (Garage had a roof) it may have been helpful to point it at the dancefloor to get another 2-3 feet of reach (meaning physical distance, I know subs are omnidirectional). Seeing as it wasn't enclosed i didn't get any boundary loading but even so it sounded pretty good.
Side note:
Last weekend I was off-roading in my Ford focus wagon and well lets just say I killed the engine by taking up water in a stream crossing. Therefore I am carless indefinitely

Next vehicle I get will be a truck as I was able to fill an entire bed of a medium sized truck with just my speakers/ stands/amp rack.