Since Tom posted first I'll just add my comments to his thread.
I got my screen and eagerly set it up last night, so these are initial impressions.
I agree with Tom's comments about packing. I used to work in the damage and rewrap section of UPS, and most of the damaged parcels were due to poor packing. My screen came in two boxes. One was a thick cardboard tube with the screen material rolled up, and the other was a long rectangular box with the frame.
Everything was wrapped internally with paper, plastic or foam, with packing between pieces. This was really nicely done, and most welcome because the worst thing would be having to return the screen even before starting installation because of shipping damage.
I made a mistake in my sizing dimensions, even though Don asked detailed questions as to screen size. I had made my last screen frame, and my two previous screens before that had the snaps and black screen edging about 1" thick and butted up against the outside edge of the screen frame.
The Stewart screen frame was a nice black velvet edged model, where the screen material snapped in from behind and there was a beveled "picture frame" edging on the frame face that extended about an inch on all sides beyond the screen material edge, and roughly 3" beyond the viewable image size.
Unfortunately, this made the frame about 2+" taller than my lowest ceiling beam, and I had to notch the beam to fit the screen in. Still, it's nice and snug now, and all of the frame pieces fit together perfectly. If you are considering a fixed frame and have tight area diminsions, remember to figure in the outside frame size (OD) when ordering the screen.
The screen already is smooth, where some of my past screens took a while to smooth out fully. Also it's important to mention that even though I can smell the vinyl screen material, my last DaLite screen had a unbearibly strong vinyl smell for at least a week, before it toned down to this level.
It was dizzying. The GrayHawk's smell is not noticable from my main seating (15' away) and will no doubt get better still with a couple days to air out.
I've seen a bright D-ILA projector on a gray painted wall, so I figured that the whites would "look" relatively white, which they do.
My expectation was that the GrayHawk screen would be grayer than it is.
On it's own it looks slightly off-white unless you set it next to a white screen.
I just set it up last night, so I haven't put the screen up side-by side with my previous screen yet for comparison, so my initial impressions are of the GrayHawk itself with my JVC G15 D-ILA FPTV with an ISCO lens.
I expected the blacks to look blacker, and they do, but not to the extent that I had thought. My FPTV is calibrated, so it already has pretty good blacks, and the measured contrast was 500:1 (not checkerboard).
My brightness was previously set to -7 with the 180" 16:9 1.0 gain DaLite perforated screen, and it is now set to -1 with the GrayHawk screen.
The biggest improvement so far was in picture detail, both in shadows and with textures. This improvement alone would be worth getting the screen for a fervent videophile.
My last projector was a Sony 1292Q which had 9" CRTs, and the added gray scale range and picture detail remind me of the better qualities of the CRT FPTV. The GrayHawk adds an exra level of picture depth that I could easily see. The impression was like wearing polarized sunglasses.
My friends that I had over to help me install the screen said it looked great, but I'm not sure if they saw a difference that I did.
I have certain demo clips like The Fifth Element, Lost in Space, A Bug's Life, and some HD demo recordings etched into my mind as far as picture detail, color goes. Everything was visually improved, and I could spot extra depth and detail in all of the clips.
My friends were stunned with the HD football footage that I had recorded, and said that I should charge admission. http://www.avsforum.com/ubb/smile.gif
The audio was clear sounding, but I still have to add the THX filter for the center channel and specifically test some DTS movies and music later.
The other improvement that I noticed was the screen perforations, which were smaller and more dense than on my DaLite screen. Previously, I could see the perforations from abot 13' away, but not from my main seating (at 15'), but now they are hardly noticable from my close seating at 8' away, which is great. There was no visible moire effect at all.
Anyway, I was up until 3AM this morning watching demo material, and I'll do more specific testing later, especially audio testing and side-by-side comparisons with my other screen, using torture material like Dark City.
I'm looking forward to seeing the DirectTV HD demo (especially the Discovery HD material) with this screen later tonight.