I have been using a Barco Graphics 800 (825 lumens), a Barco Graphics 1200 (about 1000 lumens), and currently a Barco Data 701s, which outputs about 1100 lumens peak white. The problem is not as noticeable as before, possibly because my current screen is only about 80" (diagonal, 4:3), and I have turned the material 90 degrees, and keep the excessive material behind the screen. Not sure if this turning have an impact on the gain? The previous screen was about 120" 4:3.
I was offered a piece of new material, but the shipping/VAT/customs to Norway is more than the material cost. A friend brought the material the last time. If the streaking problem is gone the M2500 would still be a candidate for my new compound curved screen.
Gunnar