Like the idea of 2.35:1 screen. I've heard good things about Grandview from a friend of mine. The price seems right.
I was going to go for no gain (total light control), until I started to look at the review of the JVC DLA-X3 3D projector in the latest Home Theater magazine. They are suggesting a screen with a little bit of gain could help alleviate the loss in brightness when viewing 3D material.
At $4,500 (that's USD though so who knows how much it would cost here), it definitely strikes the right price and the reviews seem very positive. I will likely wait until new PJ announcements in the fall to see what else is announced, or if I can get a deal on it at that time.
My thinking is 2 years from now, I'll kick myself in the rear end if I don't have 3D. I went through a similar dilemma 4 years ago when I built my 1st HT. It was about 720p vs 1080p. I bought 1080p, paid a premium, but never regretted it. I think we're almost at that juncture with 3D, especially since I have 3 other large flat screen TVs in the house, none of which does 3D.
I should mention I sold my PJ and screen to the people who bought my former house. I had a Mitsubishi HC5000 as well as a 100" Screen Innovations 16:9 fixed frame screen with no gain (1.0).
I still own a complete set of Definitive Technology ProCinema 1000 Series speakers, which I really, really like and intend on re-using here.
My receiver will likely be the Pioneer VSX-1021-K. I like the way it plays with Apple products (my entire household is Mac/Apple based), especially the Airplay compatibility. You guys will have a tough time to convince me to go with anything else given the cost / bang or the buck.
The DLA-X3 doesn't have enough light output when playing 3D on a 1.0 gain screen even on the "high" lamp setting. I know it's out of your budget, but between the 3/5/7, only the 7 that is bright enough for 3D (and you'll still need at least a 1.3 gain screen for it)