Hi Troels, I finish your DTQWT MKII design for my friend and neighbour Veselin Krachunov(will certainly assemble a pair for myself),  we have been listening to DTQWTs in my listening room (until he complete acoustic treatment of its room) with a DIY 20W SE ??70 double mono block for  few days now and they sound  promising, still waiting to fully broken in  the drivers (sound is getting better with every passing hour).
The cabs are made from 30mm MDF(front,rear and top), 18mmMDF(internal), 19mm+6mmMDF glued with a GREEN GLU (very good for damping vibrations in large panels) (side panels).
Sending you some pictures (rear grille only for the photos,still need to experiment with wool) and measurements(taken without rear grille - impedance is slightly different from your measurements, guess MKII crossover, FR - pretty good with not yet fully broken drivers) of the finished project for your bilders responce page. Thanks for the great projects, inspiring site and share knowledge and experience.
With best regards, Daniel Dotzov SOFIA,BULGARIA
P.S. -  A link to personal (and your readers): enjoyment - http://bgaudio.org/forums/viewtopic.php?f=16&t=18380&start=0