There is a solution available to solve the stretching problem with an HDMI 16x9 input. I emailed Lumagen tech support describing the problem with this projector. Here is their response:
You should try to drive your projector at it's native resolution so that the projector doesn't scale the image. There is a standard VESA mode for 800x1280. You can enter the following custom mode into the Radiance.
1. Turn on service menu by pressing "Menu 0910"
2. Enter a new mode timing for one of the custom modes by pressing "Menu, Output, Custom Modes, Custom0, Timing, Mode Timing, Ok"
3. Test the mode by clicking "Test Mode" at the right side of the screen.
4. Make sure that you "Save" the new settings.
5. To vertically squeeze the 16x10 image to 16x9 press "Menu, Output, Styles, [style], Mask/Shrink, Shrink, Ok". Adjust the top and/or bottom shrink settings to get a 16x9 image on the projector.
6. Make sure that you "Save" the new settings.
I know that the Lumagen Radiance Mini-3D Video Processor costs more than the LG 300T (There's one on Amazon for $1499) but consider this:
1. The Radiance has a complete Color Management System so you could calibrate this to be a near perfect color projector.
2. You would have the only quality HD LED projector with decent brightness for around $2,000.