I wanted to add my 2 cents. I haven't really seen anyone talk about a DIY option to installing their XD screen, like I did.
I decided to make a plywood wall for my Seymour XD screen. I had my family help "stretch" the screen while I stapled it to the frame (hundreds of staples).
There is not much stretch to this material. It installed very easily and was easy to get the waves out. It looks very tight now.
I decided to have a plywood backing to aid in support in case anyone fell into the screen.
After I trim out the outside of the screen, it will measure about 155 inches diagonal.
Be sure and paint the area behind the screen with flat black paint. When I look through the speaker cutouts, I can see an almost perfect, reverse picture. A light colored background would definitely reflect back onto the screen.