Hi rogert,
After much research, I was going to buy the smx material at just about the same time smx stopped selling the material by itself.
Additional research led me to Chris Seymour at SeymourAV. Chris sells the Sheerweave material that appears identical to smx and may, in fact, be the same stuff.
The seymourav material is acoustically transparent. With your THX Ultra's you could mount your center channel in the wall (or the center of the screen) and have correct placement for the sound source. Roy measured the material for me to see what type of EQ adjustments might be needed for the JubScala. He said it was one of the best screens he had measured and said no adjustment was necessary. SWEET!!
My acoustically transparent 60" by 107" (122" diagonal) 9:16 screen was stapled to a 1x3 velvet covered frame. Total cost of screen was about $160. The picture is awesome with my Panasonic AX-200U projector and PS3 BlueRay player. Having the center sound coming from the behind the screen is much better, too.
Call Chris. Tell him you're one of the Klipsch gang and that I suggested you call. (No affiliation, yada, yada)
Talk with him about the projectors, too. He has both the Pana AX200 and the Pana Ae2000. He said the 200 is a better projector in many ways than the 2000 at less than half the price.
http://www.seymourav.com/
515 450 5694
Keep us posted on your progress.
Blessings,
Bill