I went from a 40" 4K on my desk to the 48". I was already a bit uncomfortable on the 40" (I felt like I wasn't as quick to notice things in competitive shooters because I had to move my head) and moving the 48" to the far back of the desk pretty much matches the 40"; right on the edge of uncomfortable-but-usable. For single player immersive games it's worth it thoughI have been rocking a 40" 4k that is attached to my standing desk via arm...the PPI is such that it's in a sweet spot and I was thinking of downsizing because I don't know how much I put things in the corners...but that'd mean I'd probably be leaning and squinting a lot more, now that I think about it. But adding an extra 8" seems silly to be that up close to. About how far are you from it, and do you use the corners much? Any simulates monitor borders using software that divides the screen?
I suppose I could wall mount it and move my standing desk back, I just don't know if I want it to come to that, as I like my monitor moving with my height.
Desktop use definitely ends up with wasted space; I find myself moving things to the corner and treating it as a smaller monitor a lot. And the 48CX I'm still getting used to the weird subpixel arrangement which is enough to be bothersome
Hopefully the Gsync and HDMI 2.1 issues get ironed out. Without those I'm not sure the upgrade was worth it