On the other side of things, running dual 4k displays for anything remotely intensive (a browser, IDE, instant messaging, mail client, and terminal in my case)

On the other side of things, running dual 4k displays for anything remotely intensive (a browser, IDE, instant messaging, mail client, and terminal in my case) can bring some machines to a crawl or run the fans at high speeds indefinitely. I think graphics technology has to catch up to hiDPI before I'd go past 4k. And let's not even get into the fact that 4k 60hz is a struggle and a half -- you need HDMI 2.0 or displayport to make it work at all, and many modern laptops lack either port, forcing you to use USB-C/thunderbolt with adapters that have poor spec support and even worse documentation. Even if someone offered me dual 5k displays to replace my dual 4k ones, I would turn them down right now. Before we move on to 5k displays, we need to get 4k60 down. And while I'm on my soapbox... where the hell is 4k90 or 4k120? I only bought my 4k monitors last month, with virtually unlimited budget, but they just don't exist. I imagine they've fallen victim to the same issue: the cables to support it just barely exist, and certainly can't be doubled up for dual monitor setups without a mess of wires plugged directly into a laptop or desktop.