Sounds good! I think it is money well spent. I too just took the plunge and moved from a 60" Plasma.
I have a dark light controlled room, but so far I feel like I want better black levels and contrast. Coming from Plasma, I am used to the deep blacks and great contrast. I think my biggest problem is when the screen is off on the Plasma, you see a dark grey / almost black screen. When you turn the projector off, you have a much larger all white screen that is still visible when it is close to pitch black in the room. I think a grey screen is what I want. What is funny to me is many people say that you don't need to worry about a grey screen as these 5030UB's have very good blacks and contrast. I took my projector to my brother in laws and he has an older Panoview Grey Wolf II screen that is grey and 1.8 gain. I have to say the image looked great and the sparkles from the screen were minimal and only apparent on very bright scenes.
What I have learned is in a completely dark room, his screen looked good and my blackout cloth looked terrible. I tried a matte white 1.0 gain cheap screen from Best Buy and it is better than the blackout cloth, but not nearly as good as my brother in law's screen.
From the little I know and understand, if you have a bright room the screen is going to be a major piece of the puzzle. I guess it really comes down to how much you want to replicate having a "big TV" that you can watch all hours. Unfortunately a Black Diamond screen from SI is almost as much as the projector
. There are alternatives, but I would spend the time figuring out screen gain, color and how much ambient light reduction you will want and the trade offs involved.
Using the wall to figure out screen size is perfect and will give you an idea of what it looks like with daylight pouring in and when it is dark at night.
Good luck and enjoy your new purchase!