I've made DIY screen out of white duck cloth from Walmart ($3/yard X 60" width), white blackout cloth ($5/yard X 54" width), and glossy white tile board (4'X8'). I'm settling on the commercial Dalite Video Spectra with 1.5 gain (96" X 72") Model B for $150 shipped from
www.francisav.com . The DIY screen does not look as professional and does not have the slight gain that I like with the Video Spectra. This gain is not as drastic as High Power or Glass-beaded of Dalite so my blacks are still preserved. Combined with my Hoya FL-D optical filter and clear color wheel painting, my LT150 gives very nice image. Downside for a roll-down is few waves at top of screen which can be resolved if you cut it off the roll and stretched it on a frame or wall. I prefer the roll-down for traveling convenience and easier hanging. I can live with a few minor waves (not very distracting unless you look for this on slow horizontal pans).