While we agree much, I still wonder if we mean the same thing by even lighting on the $69 Kindle cover, new? By uneven I simply mean the light brightness varies depending where on the page one measures it. The $69 Kindle cover light of course isn't splotchy like PW can be.
All $69 Kindle 4/4B covers I've seen hotspot near under the light and then go on to become a little dimmer towards the sides. By hotspotting I mean an area shows a brighter circular glow of the light where it biggest hits the surface. Even if the sides don't look dimmer to you, are you saying yours' doesn't hotspot either?
Now I understand you use a filter on your lamp, so obviously I mean an unmodded light.
Here is my photo of three different $69 Kindle lighted cases from the first posts of this thread, all showing the hotspot and lighting unevenness - brighter in top middle and less bright towards the sides and bottom (a more careful look finds the more subtle differences like LEDs pointing a little differently):
Bigger image:
http://imageshack.us/a/img27/6820/pdme.jpg