I've tried this on several projectors including (Benq, Optoma) as listed. The description mentions that you can use this with projectors that have 3 screw holes. Somehow I doubt they checked it. While you can line up the brackets (very difficult) with the holes on the projector, the problem is that you can't rotate the bracket. Therefore, you end up with a projector oriented at an angle of 45 to 90 degrees from the wall/screen. You forgot to list that you should be completely perpendicular to the screen after you have successfully aligned the mounting holes. This is probably easier with a large 4-hole projector, but nearly impossible with a 3-hole projector.
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