Using  a Da-lite 5000 lumen overhead projector ( OHP ) with a 410w lamp and Goodmans stripped Lcd monitor panel I compared the projected image on samples of 15 types of  Da-lite projection screens and blackout cloth . The descriptions and light gains listed are taken from the Da-lite info that came with each sample .

    The projection screen samples are attached to a standard sheet of foam board in no particular order . The Goodman stripped Lcd  was set to a color temperature of 5800 thru the OSD ,  the brightness at 65, contrast at 60. All other setting were left at the monitor defaults. This is a standard overhead projector  with a triplet lens . The screen that the foam board is attached to is triple pass blackout cloth  with a 70-72" diagonal projection. The pictures were taken with a Canon SLR 35mm camera, 800 speed film at an exposure of 1 sec.
    To see how these screen samples react to lower lumen output, I set the overhead projector to the "lamp life saver "setting standard on most OHPs.  This setting is supposed to extend the lamp life 20-25% and I assume it also reduces the light output by the same amount. I'm not really sure of that but, it sounded good. Below is a chart showing the placement, samples name and light gain of each sample piece.
 

Da-lite screen sample placement on foam board
   

    The pictures were taken at about 8:00pm. Some of the pix are taken with one lamp with a 60w bulb on in the same room. The lamp is about 8-10 feet in front of the screen and at about a 45 degrees angle to the side, almost inline with the camera distance. They will be identified as such.

    The first movie I used was "Blood Rayne". As you know Vampires burn up in natural sunlight sooooo, as you can imagine the movies is filmed almost exclusively at night or with the look of candle light.  The second movie is "Stick it". Gymnastics and lots of color. Sorry, I don't do Nero, DIYgirl or The Fifth Element.

    The samples are approx. 6.5" x 6.5". Some of the sample are puckered looking, this is how they were shipped . I couldn't straighten them out and I didn't want to cut the puckered part off making the sample too small , so I used them as is.
 

In some of the test shots I took with this lamp on in the room and the pictures are identified as lamp "ON"

The Da-lite "High power" sample in this test looked dramatically washed out from directly in front of the screen. This is exactly how it looked. Early on in the test I made a comment to my wife about how white the sample looked. She was sitting on the couch  at about a 45 degree angle to the screen and she said, " What are you talking about , I don't see any white samples". Only when she came over to the camera in front did she see how white the sample was. What caused this?. I don't know. My only explanation of why the High Power and the Glass bead sample seem washed out is that with my throw distance of  7-8' the high gain screens are receiving too much light from the projector. Possibly, the high gains should only be used with longer throw distances.