W20000 Audible Noise Levels
I just don't know, the W20000 seems quieter than older BenQ projectors. True, they have also lowered the claimed noise level to a respectable 28 db at full power, and 25 db at low power. In most environments below 30 db is a non-issue, you might barely notice it during a dead quiet scene, depending how close you sit. I acknowledge that there are some folks who really do not want to ever hear their projector. Even for them 25 db should do the trick. I don't measure noise levels (it's complicated, multiple points), so I'm going on published specs and being in the room with the projectors. The noisiest home theater projectors tend to claim 31 to 34 db at full power.
Even in full power, the W20000 is reasonably quiet. A very tiny few might take exception. I'd say that the W20000 is a little quieter than average. Generally DLP projectors are the noisier ones, and none of the DLP's can match the quietest 3LCD (in one or two cases, full power at 20db or below).
For perspective, if I have the projector on, and the sound all the way down, when the air conditioning kicks on, it is at least a magnitude louder, completely, and easily drowning out the projector. The projector currently is sitting less than 4 feet behind me on an angle, and I'm sitting in a leather captain's chair, so not very sound absorbing, but blocking direct "line of sound".
W20000 Projector Screen Recommendations
With all those lumens to spare, I can't help but recommending a high contrast gray screen surface as my first choice. I favored the W20000 projector, when watching on my Firehawk, over using my Carada Brilliant white screen (claimed gain 1.4).
A high contrast gray surface will lower black levels slightly, and also reject some side ambient light (a plus for many). With my 106" Carada, for serious watching, I'd close down the iris a bit, because those letter boxes are a bit bright, due to those roughly 700 lumens, in best mode. With my slightly larger Firehawk (from where I position the test projectors in that room, I could only get about 115" diagonal maximum).
The thing is, when you have a really good projector, almost any screen will do, but pairing the projector with the best screen for your type of viewing and your room conditions will further improve your viewing experience.
Bottom line: First choice a high contrast gray screen such as the Firehawk G3, the Grayhawk RS, Da-lite HC Da-Mat and HC CinemaVision, Elite High Contrast Gray, Carada Hi-Contrast Gray, and equivalent screens from Draper, Grandview and others.