I've been playing around with modeling this subwoofer. It lookes good if the WINISD PRO model is accurate.
TC Sounds Epic 12 $193 parts express
O Audo 500w amp $211
only 5.5 ft3
112db at 18hz looks to be within 1.5db all the way up
I checked: cone exursion, vent velocity, amplifier apparent load
looks good as far as I can tell.
edit how come I can't attach a Winisd model file?