The BenQ MX631ST is a short throw projector intended for use in classrooms or conference rooms. It is a single chip DLP XGA projector that in its brightest mode is specified to produce 3200 lumens and its lamp is rated to have an unsually long life of up to 10,000 hours, in SmartEco mode. Even when operated in the full power (i.e, "normal") mode, the lamp is rated at a fairly long 4,500 hours life.
This is a XGA resolution projector (i.e., 1024 x 768) with a 4 x 3 aspect ratio as is typical for many entry-level business and classroom projectors. However, since many classrooms and conference rooms are already equipped with 4 x 3 aspect ratio projection screens, the MX631ST is certainly a viable choice when replacing an existing XGA projector.