So I picked up a 65" from Costco over the weekend to test out, personally my main focus is the performance of the Android TV operating system since I only want a TV with this OS as opposed to anything else (someday everyone else will catch on).
I had seen the concerns over the performance of this OS on the older F generations (especially the 900F) though I have no actual hands on experience of them. I have seen people commenting that the new 950G was MUCH better and closer (if not the same as) the experience you get with a Nvidia Shield TV which is hands down the best streamer and Android TV box out there. Lots of people said that the new 850G TV's should have the same new SoC as the 950G or at least the same level of performance in Android TV but I couldn't find to many concrete details about what SoC the 850G was actually using and worse, I was seeing some conflicting reports.
Now, again, keep in mind I have absolutely no hands on experience with the F generation of TVs however, my ONLY experience of Android TV to date has been two Nvidia Shield TVs which I love so, with that in mind, I cannot compare how the 850G performs in comparison to the F generation of TVs but I CAN say that the Android TV OS on the 850G pretty much performs very closely to my Nvidia Shield TVs and at the very least, even if I have no hard performance data to compare, I can tell you that it performs completely acceptably well!
Now, it's entirely possible that it's the same SoC/same performance as the previous F generation of TVs but in that case, I really don't understand what all the complaints are about having coming from the Shield TV myself.
As for the picture? Meh, it's as you'd expect for an edge lit TV, you're not going to be blown away by it in any stretch of the imagination, does it do the job though? Yes, absolutely and more importantly, with Android TV.