The size thing is what I consider extremely important all kidding aside. I have brought my projector home a few times and even in a 35 x 18 hall with 16ft. vaulted ceiling, my wife got nauseous (and lsu was winning) watching on the 13 ft. screen. As the Sonys were....gratuities, let's say, I could have gotten any size I wanted. I made a cutout from a piece of cardboard and let my wife pick the size for the informal living room (the br space was non-negotiable due to the cabinetry). The 18" swingout mount was a compromise for me not getting a 50"