Last night I painted half of my screen with Behr's "Snowfield" (the other half was Behr's Ultra Pure White). While I was watching Austin Powers my wife came in, so I asked her which image she liked better. With the movie playing, you can't tell which color the screen is painted. She immediately said that she prefered the side that was painted with the grey "Snowfield". I have to agree ... the blacks were MUCH better and the colors appeared richer and more saturated. The whites were'nt as bright (obviously), but after I painted the entire screen grey, it was a non-issue. I wouldn't say that the whiter whites were better -- they were just different, and the better blacks / richer colors was well worth the switch.
Just thought I'd share this since everyone seems to be touting high gain screens with the LT150. For me ... I like the grey screen. I must also mention that I have total light control in my room and that my screen is 92 inches wide. The Snowfield is also the lightest of the greys available from Behr at Home Depot. In a light room you might mistaken it for a shade of white.