I believe it may have something to do with NEC's video software in the projector (Vortex) which adds to the cost. Improved colors, also LT-150 will accept progressive input and I think (not 100% sure) you can turn off the clear section in the color wheel when using this input. I am planning to buy the Sharp PG-M10s and if you are planning to run HTPC most of these differences wont come into play. You can also set a higher refresh rate with the lt-150 if you plan to use HTPC to further minimise the rainbow effect. lt-150 will go up to 117hz, Sharp 85hz (of course this will depend on projectors tolerance at these higher levels: tearing etc...) hope this helps a bit. Price may also come into it where they are made. May want to look into this. cheers Steve