W10000 Projector: Projection Screen Recommendations
I'll start by saying that the W10000 matches up extremely well with my Firehawk screen - a light gray high contrast surface. I'm very pleased with the combination. I have, however thought about replacing the surface with Stewart's Studiotek 130 white surface (considered by many to be the industry standard). I do, however have to deal with some side ambient light in my theater room, so, I'm sticking with the Firehawk for now.
In my testing room, though, I have a 106" Carada Brilliant White, with a 1.4 gain (measured 1.3). In cinema mode, with the iris wide open, I actually found the image to be almost too bright. I actually closed down the iris about 1/3 of the way. That also, by lowering brightness, reduced black levels to what I find more acceptable.
i would therefore say, that if you want a large screen (110" and up, the Studiotek 130, Carada Brilliant White, or similar screens from Da-lite, etc.) are a definite option, as the W10000 produces more than good enough black levels to skip the HC gray surfaces. You still have the option of staying with white surfaces on smaller screens thanks to the iris.
If you have a fully darkened room, therefore, these white screens are a very good choice. If you have any side ambient lighting to deal with, though look to the HC grays, or even a gray (Like the Elite Cinetension or ezFrame with their HC gray surface (which has very little HC).
About the only thing I would stay away from are really dark gray surfaces, like Stewart's Grayhawk, and others, which were designed for older LCD projectors with contrast ratios down below 1000 (way below 1000).
While there are good affordable choices (if you are putting just about your whole budget into affording the W10000), from Carada and others, my own two cents is that the Firehawk is an exceptional screen, and worth serious consideration if budget allows. Screens do make a difference.