Looking for Answers about LED TV?

A co-worker purchased the 8000 series, I have the 6000 series. Our office purchased the 8500 series. The 6000/7000/8000 series all use edge lighting LEDs, which produce a fairly uniform/consistent light level across the entire picture. The 8500 series uses back lighting LEDs (in groups), which can be dimmed in groups or individually, to help with contrast. For example, if a scene is all dark (think night outdoor shot) with a character walking around using a flashlight, the area of dark would dim its groups of LEDs and the area of the flashlight's beam would increase the output of the LEDs. Note that there are only a hundred or so groups, so it isn't a perfect match to the resolution of the TV (which has 2.1 million pixels), so sometimes there will be light bleed over (flashlight beam causes bright LED light, bleeding outside of the beam to the dark area around it). Also, the software that determines which groups to dim and how much to dim them do so by averaging, so small specks of light in a large expanse of darkness (such as stars in the midnight sky) will be dimmed out. However, in most viewing, the 8500 series produced a little bit better contrast than the 6000 or 8000 series.