Make sure you use the flat terrain shadows and the 1070 will run 4k very well. I can fly through the Las Vegas Strip with 60fps, but in the Caucasus fps dips sometimes over large cities.
Another thing, turn off anti-aliasing. You do not need it with 4k!
And for the price they are too small, imo. I use a 40" Samsung TV in 3840x2160 for DCS and I couldn't go back to a smaller display.