They're too different. If those are your options, you don't need a detailed comparison to any particular 4K display. Question is just whether or not you need 5K
No, that's what
you have decided. Other people are trying to decide whether 5k is worth the premium.
Plus, thanks to the history of the iMac, 5k is the "gold standard" for Mac displays - and the ~220ppi resolution of the 5k iMac/Studio Display - which plays a large part in how people perceive display quality - is a rough standard for all Apple displays. So it's the obvious basis for comparison,
Most people don't, so they ought to ignore the Studio Display and start comparing the M8 against the tons of other 4K options.
Sure, a massive round-up of 4k displays and how well they work with MacOS would be great. However, what would
also be great is a more in-depth comparison of 4k and 5k screens in general - preferably with an emphasis on what they were like to
use for various tasks rather than climbing up on the desk with a magnifying glass and hunting for pixels.
The M8 might not be the best 4k display on the market but it stands out because of the vaguely Mac-like styling and the bundled webcam, which will influence many Mac users looking for an iMac alternative.
You know, sometimes people like some help in deciding whether they need a pick-up truck or a sports convertible. They'll both take you to 90% of the same places.
There are LG and Dell 5K displays. It's definitely a less popular option.
Pretty sure the Dell is discontinued - and good luck finding an LG at the moment.
No one runs 5K 27” displays at 5K-sized resolution. The display double pixels to 2560x1440.
Let's just clarify what "doubling pixels" means here: "looks like 2560x1440" mode on a 5k 27" display
is 5k resolution (~220ppi/"HiDPI"). Literal "pixel doubling" (i.e. showing a 2x2 block of pixels for each pixel in the source) only happens when running ancient pre-retina software that doesn't recognise 'HiDPI" mode or doesn't include bitmap assets for retina screens. Everything else is rendered at the full resolution of the screen. System fonts, icons, dialogues are displayed with twice the number of (linear) pixels to make them the same
physical size that they would be on a 2560x1440p screen, but they contain far more detail.
In any application that lets you set a zoom, choose a font size etc. you can scale the actual content that you're working on and it will take full advantage of the sharpness of the 5k screen, giving you more "real estate*" than on a lower-res screen.
You need to jump through hoops to change the
actual resolution (as of Mojave, option-click on 'scaled' in Display Preferences, and then check 'show low resolution modes'). Otherwise, you're just choosing between two types of scaling: 2:1, as above, or non-integer which works by rendering internally to
twice the chosen "looks like" resolution and then re-sampling it to the native resolution of the screen - which is still a lot better than just stretching stuff to match the screen.
Likewise, on a 4k screen "looks like 1920x1080" is actually full 3840x2160 resolution with 2:1 scaling. You're
not wasting your 4k screen by running it at 1080p. The snag is, 2:1 makes the UI elements a bit too big on a 27" or larger display, until you get to 32"+ where 1:1 starts to get usable.
(* The problem with the term "real estate" is that people act like it is some objective measure when in fact, it's a complex function of your preferred viewing distance, your eyesight, what software you are using and how you are using it.)
