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 Srinivas Johnson

I've had this lamp for 30 days now and everything looks fine. I plugged it in even though my other lamp was fine, but got a message saying the lamp had expired. This only lasts with a 90-day guarantee. I bought this lamp a bit more expensive because it was one of the few promising OE parts. If it lasts, another will likely be sourced as this part is no longer available from Optoma.