The situation is far worse when it comes to 4k displays.
This has been thoroughly discussed on this forum already, but 4k at 28" really just requires a better scaling approach or it's useless. Otherwise all that would make sense would be a 24" 4k display or 5k for everything above (since only the x2 mode makes sense for the true retina experience.) and we need the screen estate of the current 2560 resolution on the apple thunderbolt display on any future 4k screens, but at retina resolution.
I am just so damn curious how they will figure this matter out. It's frustrating to have a nMP standing around and no proper display available yet..