Picture is absolutely fantastic sound quality is not good that's why we purchased a Sony soundbar to go along with it so now the sound is great. I had an issue with redeeming the free HD movie that was included with the TV and spent hours on the phone with Google and Sony finally solved the issue myself.
Just purchased the X900F because it appears to be about the best non OLED 4K TV Sony makes. It took a lot of time for 1 person to put together and setup. The setup pictures were terrible. A few words would have helped a lot. I had some strange issues trying to connect to my 5ghz network connection. I had use the 2.4ghz for now. The setup needed a Google account and I did not have time to figure out my logon info during the setup. I set that up later. I find it difficult to locate things from the Home screen. It is much different than my previous Sony TVs for setting up. At this point I still need to review everything and make sure all is well. TV works great. Trying to get the second HDMI cable into HDMI3 was a beast. I dont understand why Sony went to vertical slots. Its very hard to fit the cable into the HDMI3 slot for my Home Theater.
The Android tv processor could be a little faster but that is being nit picky. The Motion Clarity on this tv and it is fantastic honestly its a really great tv for a good price. But im extremely happy.