[muzz]

You'll see waves in an untensioned pull down screen easier than small imperfections in the walls IMO.

I have some small imperfections on my walls, that I can easily see up close, but aren't noticeable from 10' away on a 115" screen..
I could probably find them if I went up to the screen, located them, and then KNEW EXACTLY where to look, but thats like begging for someone to show you what DLP Rainbow effects look like, so you can see them anytime you want to.

I don't go searching for them.

JMO