Greyhawk VS Da-Lite Da-mat & High Contract Da-Mat

I'm trying to decide between the Greyhawk, the Da-Lite Da-mat and the Da-Lite High Contrast Da-mat.


Screen Size: 45X80


Environment: No direct sun light. However, room will have some defused light come in through cellular (fabric) shades. The room can be made fairly dim, but not dark during the day time.


Projector: VW10HT


Comments:

I've searched a bit in the forums about performance, and it seems clear that people do like the greyhawk. It seems most of the greyhawk reviews are based on a better (read darker) home theater environment than I have. I've read that the Da-Lite Da-Matt is a good all around surface and very flexible. I've seen very few reference to the Da-lite High Contract Da-Mat. It's been noted that it's darker than the greyhawk and may not perform as well. Finally, I'd like to have a solution that will allow me to use the lower light mode on the VW10HT and not have to go high power.


My Questions:

1) Is the greyhawk a good candidate in a room that will not have the best light control during the day time? Or will the presence of light off set the contrast too much and produce a washed out image?


2) Would it be fair to say because the High Contrast Da-Mat is darker than the Greyhawk it will perform worse in lighted conditions?


3) Overall, considering the projector and environment which is the best screen?