Agreed 100%. Just got a new Mac setup (MBP w/ Touchbar and 27" LG Ultrafine 5k). Single cable that carries video, power, data is epic.
You can scale the UI, but the monitor just so pleasant at 1/4 effective res. Embrace cmd + tab. And tmux.
Would you prefer using two of those 5k monitors? I'm curious. I bought two nice LG 4k monitors for less than the price of one of those 5k monitors, and I'm pretty happy with my workflow now. Admittedly, it's a two-cable situation.
I've got one of the LG 5K monitors being delivered tomorrow and I'm worried I'll end up wanting a second one... guess we'll find out soon.
I prefer a single monitor. Maybe that's a result of my mild ADD