Which monitor better?

4K is not even 1080ті shows 60 fps on max settings, what can we say about 1070. And another question, do 1070 as much as 144 frame 144 Hertz in Quad HD. So if you upgrade to more powerful hardware later, and 4K can take, and if not - then you will be limited to Quad HD, and the floor logic sometime in the future there will be a new 4K monitors with some fancy pieces of the same type 144 Hz, and can be updated for example to the NVIDIA Volta (provided that it will pull 4K rules) and get a new monitor.

And, by the way, NVIDIA has a feature in the drivers (do not remember the name, need to Google) that allows you to enable 4K or Quad HD on Monica full HD, so might as well try now as 1070 will pull the game in 4K and Quad HD, and then think what to take.

Games are becoming more and more greedy to VRAM. On the monitor 27 in GTA 5 on the max. graphics settings at 144 Hz Qhd. requires more than 12 GB. of video memory. 1070-Oh max. not enough, in my opinion, and 1080-ti is not enough. A lot of memory taken additional graphics options . 1070-Oh with graphics settings about 3 GB. 90-140 Fps which is very good because no lag , no subsidence fps.