Review on OPTOMA Technology Replacement Projector Lamp for TX542/EX542/TX540/GT360/GT720/ES523ST/EW533ST/GT700/TX542-3D PRO450W/PRO180ST (BL-FP180E) - High-Quality Lamp Replacement for Optimal Projection Performance by Chris Hossain

Original OEM lamp lasted 4 years. The first replacement bulb we ordered lasted almost 2.5 years so we figured we'd get a similar cost but not that much. The second replacement worked for about 5 months, almost a day, and then died. This bulb has not been overused or abused. Used about 25-30 hours a month, about 150 hours in total. Disappointed with the lifespan of this bulb. I gave two stars because the first change was so-so and the second was terrible. Maybe different quality from different sellers?!? I am not sure. Definitely not OEM quality.