I retrofitted my basement family room six years ago and was able to do rear projection. For me, it was easier to do and, aesthetically, more pleasing. I have been very satisfied and while there wasn't a lot of information at the time regarding how to best do this, I took the plunge. Most of the advantages are obvious and a few were personal preference, but they include the following:
1) I had 20' of unfinished basement behind the planned screen wall position. I was lucky. In the finished portion of the basement, drywall was already on the walls and ceiling. Opening up finished walls for power and cable was something I didn't want to do. I could easily see my home theater project becoming a bigger basement renovation project.
2) I don't like equipment in the room. It's a personal preference. I was able to wall mount the AV equipment in the back of the room, but there are no large speakers on the floor at the front of the room, there are no shelves with rows of CD's/blu-rays, no projector hanging from the ceiling, and no signs of equipment manufacturers that I often see. Large bookshelf speakers were positioned on shelves behind the screen wall. People could walk in front of the screen without interfering with the image. Additionally, there are were no concerns regarding projector light leakage or fan noise. Why tear into the ceiling then have those issues.
3) Virtually no limitations on projector placement. The projector mount could be mounted on an unfinished ceiling behind the screen and could easily be moved forward/backward, left/right, up/down as necessary. Future projectors could be bought having different installation requirements without any of them being a concern.
Again, I realize I was lucky, but I've been so pleased that I can't ever imagine this design not being my first preference if I were to ever do it again.