I bought the Samsung 65" JS9500 on Friday. I'm coming from a Kuro Elite Pro-111FD, for reference. The colors and the blacks on the set were gorgeous! I was surprised by how well it handled motion and Game mode was especially responsive. Except I didn't keep the TV.
For $5000, I just couldn't justify it. It also had one stuck red pixel ride in the center of the TV. For the money, I expected zero. Also, My receiver is about 5 years old now and doesn't handle 3D or 4K, so I'd wind up having to spend another $1000 to upgrade my AVR, and we all know this year's models aren't up to snuff with the HDMI specs, either.
The JS9500 doesn't tick all the boxes for UHD Blu-Rays and I felt being right in the middle of the specifications being announced, I'd be better of waiting until next year's models. In addition, the JS9500 does have some of the issues LCDs exhibit (some light bleed, blooming), which did take some adjustment. Hopefully, by next year, the OLED 4k panels will be cheaper, more manufacturers, and fit the specs for UHD. If not, then I know I can count on Samsung's flagship offering.
It was hard giving up the TV, that is for sure. All in all, 4k not withstanding, the JS9500 felt like a sidegrade to my Kuro than a true upgrade, picture quality wise.