I think I've decided I'm going to go ahead and try building my own screen, on the theory that if it works out I will have saved myself a bunch of money, and if it doesn't I won't have wasted much. With that being said, should I finish the screen with a white finish or a grey finish? I have a room where I will have excellent light control. The room is 16.5 feet wide and 18 feet long. The walls will be dark colored. I know I've read that grey screens provide better black levels when there is difficulty controlling ambient light. Is that still an issue when I can control ambient light sources? Are there any advantages to a white screen? What are the pros and cons of each type of screen? What would people here recommend? Thanks!