Sealed Subwoofer Recommendation

I am looking for a good sealed subwoofer that'll integrate well with my Dynaudio Evidence Temptation speakers. I have a tremendously large room that suck out bottom 1/2 octave of bass from my speakers and I don't feel like upgrading to Master model and pay five figure more to obtain the bottom 1/2 octave. I've tried Velodyne DD15 and it worked somewhat but found it to be too slow and loose sounding. Up for consideration is JL Audio Fathom F113 that Absolute Sound and Home Theater praised but one of my friends say that this is one of those King Kong subs that is not very articulate and he recommends Focal SW 1000 Be. Anybody heard this? Has anyone heard Zu's Method which is dual 15 inch paper cone sealed subwoofers? How about Martin Logan Descent or VMPS very large array? Or Dynaudio Sub 500?