"None better than this" certainly implies it's one of, if not THE, best air coolers around. It will be as good as you can get without a pricier CLC cooler that are not much better.
Just be sure the case will fit it (look at case specs as the website it will show clearance, same with cooler, specs show the height).
As for 4K gaming... A single 1080Ti can run many titles at high+ not using AA and get 60 FPS. The higher res you go, the less AA is needed so the image still looks solid. 4K is really on the edge of being 1 card capable. Personally, I would get one of hte monitors l inked above and a single 1080Ti. Next gen 4K gaming will be in better shape and monitor pricing will go down as well as high hz monitors. I plan to make that jump in maybe 3 years, 2 more GPU generations ahead.