So I finally had some listening time on my Treos with the two 2Wqs using the M5-HP Boxes. I have a Rogue Audio ST-90 Amp, which has a 200 ohm input impedence. I set the boxes using the corrected values for the 2WQ (not the values on the boxes which correspond to the Model 5, 7, and Quatro).
I have to say that when I opened the boxes, I had a moment of "I can't believe these things retail for close to $1,000" moment. It's not that they aren't well made - they are solid. It's just a lot of money for a couple of boxes and some misc. circuitry, caps, resistors and a Duracell Ultra soldering (yes, soldered) in.
Any reservations ended when I turned on the system, though. These things made a huge difference in the sound. The bass was better, and the main speakers sounded clearer, better defined. I had to actually change my subwoofer settings - I took the Q contour down (towards tighter) by one stop, and turned the gain down one stop as well. A Tori Amos CD I played was actually breathtaking...her presence in the room with me.
I think these are a no-brainer for all users of anything Vandersteen than is high-passed - even the 2WQs with model 1's or 2's. It is a lot of money, but the sound is well worth it (look for them used, but remember you will need new batteries most likely).