Wow, two totally different things.
1. Take a look at
www.projectorcentral.com - Great sight for some detailed info on the projectors and alternatives as well as a lot of articles that you will want to read before considering a projector.
2. If you can't control the light in the room, and there will be a fair amount of light in the room, and you want to use the projector with all that light in the room, the image quality will suffer drastically.
3. Not sure if $3300 is a great price for a open box item. The 80" screen is maybe a $200.00 item. But the projector has a lot of competition from Panasonic and some DLP models in the $1,500 - $2,500 (US) price range. Making the transition to CDN$ should still keep the cost near what you are looking at for new in box items. Just a thought.
Rear projection TVs are easy - it is as simple as that. But, front projection and 80"+ screens (mine is 92" wide) are stunning. They require some work and planning, but the end result will keep you out of movie theaters and even dread going to them. I much prefer a movie at home over a theater. The sound is better, my seats are always perfect, and during Titanic with a big soda... I have a pause button.