Seconded. 2560x1440 on a 27" panel is only 109 pixels per inch. I use a ThinkPad with that same resolution on a 14" display, with a 24" 4K UHD next to it in portrait mode.
Both displays are around 200 pixels per inch, plus or minus. It's great not having to see the pixels, so much more pleasant and easy on the eyes.
Also the combination of a portrait display with the landscape display is really nice. I can read an entire PDF page without scrolling.
I agree that having higher PPI is great, but are you using scaling to make text larger? I was barely able to use a 28" 4k a 100%, can't imagine doing that at 24"
Yes, I should have mentioned that I'm using Windows 10 with 225% scaling on both the 4K UHD 24" display (187 DPI) and the WQHD 14" (210 DPI). Some people like a bit less scaling, some more, but in general you want a scaling factor that roughly matches your display's pixels per inch.
The original Windows "standard display" was assumed to be around 96 DPI. That's the monitor that 100% scaling (i.e. no scaling) is intended for. Round the 96 up to 100 and we can say that in rough terms, the percentage scaling should be in the neighborhood of the monitor's DPI.
So monitors in the 200 DPI range are best at around 200% scaling.
A 28" 4K UHD has 157 DPI, so I wouldn't want to try it at 100% scaling - ouch. It ought to be running in the 150-175% scaling range.
The idea with a high-DPI monitor isn't to make everything smaller on the screen, it's to make everything sharper and more detailed. When you double the DPI and scale appropriately, you get four times the number of pixels for everything you put on the screen.
> A 28" 4K UHD has 157 dpi, so I wouldn't want to try it at 100% scaling - ouch. It ought to be running in the 150-175% scaling range.
That’s not how it works. Lower dpi does not somehow give you more real estate!
You should still be running with ~200% scaling because you are viewing it at a greater distance.
Optimal viewing distance, assuming 16:9 ratio, is 120 cm vs 140 cm for 24" vs 28", respectively[1]. Accounting for the difference gets you ~155 ppd with both monitors[2][3], maintaining 25.0° horizontal viewing angle.
The closer your viewing distance the more ppi you need for the same density. That 28" is not inferior to the 24", when you account for distance, despite the lower ppi, because the greater viewing distance makes the pixels look smaller, thus creating more dense image.
Both displays are around 200 pixels per inch, plus or minus. It's great not having to see the pixels, so much more pleasant and easy on the eyes.
Also the combination of a portrait display with the landscape display is really nice. I can read an entire PDF page without scrolling.