I continue to be amazed by this. The BD screens are amazing, but they tend to work best with brighter projectors rather than home theater models from what I've experienced. They also are a Band-Aid to a very poor viewing environment.
I agree with Isiberian on this... If you aren't going to get the room fixed, then a front projector is going to be compromised every single time you go an use it. Models like the Epson 6020 or the nicer Sony model are, IMO, wasted when put in rooms that are weak. This is because the great black levels these models produce can't be achieved in that room. When light starts bouncing off of walls in the space the contrast ratio is significantly impacted.
That is why there is a fairly serious list of 'living room' projectors which is out there. They are brighter and have lower contrast, but deliver a solid image for a poorly lit environment.
But even then, the image is compromised, and a better solution is found in the area of the large LCD panels which Sharp (and others) are now producing.
I'm not there, but if you can, you may want to borrow a projector to see how it looks as it is in the space. The BD screens are really amazing and may deliver enough to make you very happy, but this is more personal preference than anything else. I've done front projection in the family room before myself on a grey screen... I ended up buying a plasma and moving the projector elsewhere.