If you can control the light, then I would go with a white screen. Look for units by Draper or Dalite. You can get them in your price range. As for the GreyWolf, I have one in the 92" size that I am using with my Optoma HD72 DLP pj. My pj is ceiling mounted, also, about 11' back with the pj @ 7' to the center of the lens. The picture is good with blacks being nice and deep, but you lose the gain by ceiling mounting the pj. When I stand up, the picture gets
much brighter. The GreyWolf will work better if you set the pj on a table. I don't mind losing the gain, as I think the pic is bright enough for now and the GW screens are cheap enough.
If I could use a fixed screen or would pay the big bucks, I would go with a High Contrast matte white...but I'm cheap
Edit: Check with ProjectorPeople and Visual Apex for great prices on screens. Their customer service is great, also!
You got yourself a nice pj, btw!