If you get a nicer one that supports at least 1024x768 resolution you're in for a fairly nice treat.
I think the size is limited to how large your rooms and walls are.
For me the largest I could show when I had my apartment was roughly equivalant to a
96 Inch television!
We were watching Buffy on the wall and it was amazing..
DVDs also looked great that large..
There was some fuzziness and that's because I was displaying it on my wall and not a Projector screen. But overall it was good.
The drawBacks.. you need a very dark room.
Even if you get one that outputs a lot of lumens.. it should be fairly dark in the room.
You need to worry about where to put the speakers.. When I borrowed the Projector we usually left the speakers behind everyone.. so it was a bit weird seeing the DVDs in front of you but hearing people behind ... you get use to it quick though.
Advantages..
try finding a real TV that size!
Hell if you have a big enough house I don't see why you cannot project bigger than 96" (Diagonal measurement)
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