The life & cost of a projector lamp is one reason to use a television instead. Lamps usually last 2000 hours and cost $200-$400. While a television can last decades without any replacements or repairs.
According to projectorcentral.com, 'real' 1080p projectors cost $20,000 or more. All other projectors lower the quality of 1080i to fit their native resolution.
So when you watch a 1920x1080 broadcast on a 800x600 projector, it isn't 'real' full resolution 1080i HDTV.
If you get a 1280x720 projector, then you can watch 'real' 720p HDTV, but 1080i still needs to compressed. 720p projectors cost about $3,000.
I have seen projectors with built in dvd players, but not tv tuners.
There seem to be some terrific projectors available. If I could get a projector with tuner, or a separate tuner, why buy an actual "television"? It seems like not much money can get you a bright, vivid picture of practically any size you like. And so long as the 1080i resolution is "real" rather than compressed through 800x600, what is the difference?

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