I bought the Sony XBR55X900F on 10/13/18 replacing my 2013 XBR55X900A I'm extremely happy with the overall performance and picture quality. The only thing I had to sacrifice was my 3D.
Picture and sound quality is excellent. TV is used primarily for gaming and watching movies and sports and love it. We now have three X900F in different sizes (85", 75" and 55").
I have always had great success with Sony products, particularly TV’s. This TV is more expensive than other makes but the quality is excellent. Very easy to install and excellent picture quality.