I think this screen does a good job with ambient lighting, here are a couple of shots..
Without light:
http://s168.photobucket.com/albums/u...t=IMG_1516.jpg
With 75 watt table lamp to the left of the camera- easy reading light:
http://s168.photobucket.com/albums/u...t=IMG_1517.jpg
This pic isn't too bad for a 1900 hr bulb:
This screen smokes my old Pebble Beach/2 x PTC
http://s168.photobucket.com/albums/u...t=IMG_1331.jpg 