You know, it's funny how we give each other a hard time for putting our PJ up before the room is done. I did however benifit from this and was able to eliminate a nasty problem that would have drove me nuts! When mounting your projector to the ceiling, be aware of the location of any HVAC registers/vents. When temporarily mounting my projector this last winter, I noticed a boiling type effect on the screen, (The kind of effect you see over something really hot). At first I thought the fan from my projector was blowing heat in front of the lens. After a little investigating I realized that when the furnace kicked on, the heat coming from the register was blowing into my projected image causing this VERY annoying effect. Fortunately the ceiling wasn't dry walled yet so, I was able to shorten the ductwork and bring the register closer to the wall out of the way of the projected image. So, to make a long story short, make sure you get your registers out of the way of your projected image.