Michael, the material that I have seen on my Toshiba TP71H95 (which does not do 720p), which has been converted from 720p to 1080i did not look as good as I thought it should.
My feeling was if I could display the material as broadcast it would look better.
As Marc mentioned I may have to go to a front projector... I would like to have the larger screen size, but the dollar issues have kept me out so far.
Steve