Update:
I am re-inclined towards the LG UH850V /8500 series , after contacting LG HQ in MENA / Jordan and reading users feedback mainly from Avsforum.com (
http://www.avsforum.com/forum/166-lcd-flat-panel-displays/2326849-official-lg-55-60-65-uh8500-thread.html)
1- It has a True 10 bit (not 8 bit + dithering) Panel since it a must for HDR Dobly Vision to be supported to has this perquisite , / the difference between 8 bits and 10 bits is enormous, with 8-bit color allowing for a total of only 16.8 million color mixes and only 257 possibly values for any one of the primary digital display colors –Red Green and Blue (RGB). While this sounds enormous, 10-bit color allows for just over 1 billion different colors and 1024 different values for any of the RGB colors (
http://4k.com/the-ultimate-guide-to-the-new-4k-tvs-of-2016-from-samsung-to-lg-sony-and-vizio-14496-2/)
2- It has RGB and not RGBW Panel (Pseudo 4k) that the lower UH6100, UH6500 and UH7500 has.
3-It supports Full HDR supporting (Wide Color Gamut) ,Colour Gamut (DCI P3) is 90% , which is very good compared to 2015 model from different brands and the advertised unit by Hamdan Samung KU 8350 , there is a difference between basic HDR support and Ultra Premium HDR Support (the KU series in an entry level HDR (Samusng Calls it HDR Premium) for Samsung 2016 Lines which are great in Value but not fully fledged)
4-It supports Full 1080p for Each eye in 3D Mode - Passive 4K 3D TV , and not 1,920x540 pixels (Higher Models on Sony and Samung on Supports Active 3D.
5- Reasonable Input Lag even on 2160p HDR enabled.
I was leaning towards the Samsung JS7000 series which the "son" of JS9000 having quantum dot screen and Ultra Premium Certified and great in prive value , but sadly either this model or 8 JS 8 series are available.
With those specs confirmed about the LGUH850V with discrepancies eliminated , the value/features of this model is great compared to Sony / Samung 4k Ultra Premium GDR Premium (I am pointing to Sony X850/800D Models that has a similar price range while the JS 9000/9500 Samsung offers are awesome but with price ranges that put them against OLED Models like the LG E6.
I will look for Panasonic mainly the DX 802B and DX 702B , as an final overview.