Won't work. The upscaler can change things like refresh rate and input delay (I use an upscaler for my LCD HDTV to eliminate the input lag and make my older consoles not look like arse), however since the way light emitted from a CRT is different than the way light is emitted from a plasma or LCD TV, the light gun is incapable of picking up the little white squares on the screen when the trigger is pressed when using a non-CRT. All my other games work just fine, but alas I cannot play any of my NES Zapper games on my setup.