Projector for PC/TV combo

Hi, I've been looking at HDTV's, and Projectors, wondering which would be more cost effective, the benefit of a projector is having any size screen I want, I just wanted others thoughts on image quality versus' HDTV's.

 

And the fact that I would have all my electronics hooked to it (PC, Cable, PS3, etc), I would use it probably a good 6 hours a day, which would have longer life?