Funny enough I was looking at these two TV's this past week too as well as the Sony A1 OLED (the 55" is $1k more than the LG OLED at the moment). Had a demo of the A1 connected to a Google Home, it was pretty fast with Google Play.
Between the Sony X900E and the LG, I would go with the LG. However, I am waiting to see what happens Black Friday, I reckon the 55" LG OLED may go to around $2k and the Sony A1 to $2.6k ish which would make it compelling to me.
Shaw Employee, Opinions are my own unless otherwise stated.