I recently purchased a nicely loaded up Mac mini 2018.
I also went with two of the 32" LG 32UL950-W 4K monitors. I decided on these over the 5K LG's, as they look (in my opinion) much nicer with tiny bezels, and I prefer the screen real estate of the 32" display running at "looks like 3008x1692) over a 27" at "looks like 2560x1440" but with higher DPI.
These display are Thunderbolt 3, which means you can also daisy chain two of them together off of a single connection. I can confirm this works great connected directly to the mini.
I also purchased the Blackmagic eGPU Pro, which I know is overpriced, but it also has Thunderbolt 3. This setup works nicely with the Mini. I did not perform much testing (other than seeing it works) using the internal GPU.
Now, there are a few downsides. Occasionally, when I restore my mini from sleep (this happens maybe 1 in 20 times), one of the displays comes up at the wrong resolution. Going into display settings doesn't fix it, as it doesn't show the full array of display resolutions supported by the monitor. What does work is to just switch off both monitors, and switch them back on. A tad annoying, but not end of the world. Hopefully software fixes will eventually correct this.
Then, there's the well-known (and published by Apple) FileVault limitation. If you have an eGPU, you cannot see the login display to enter your FileVault password to unlock the machine. You therefore have to plug in your monitor to another port directly on the mini, log in, then plug it back into the eGPU after. Ugh!
I thought a solution might be to use the extra HDMI port on the back of one of the monitors directly to the Mac mini. Then, on boot, I can switch the mini over to HDMI, enter my password, boot up, and switch back to Thunderbolt.
This kind of works... however, the HDMI input of the monitor continues to be an active display within OS X (even though you can't see it, because you've switched to the other input).
There are utilities out there that would let me "disable" that HDMI display.
BUT, in the end I found that whole solution with input switching to just be annoying and have since disabled FileVault. It would be really nice if Apple can figure out how to make the minis firmware support the eGPU in some capacity to allow boot screens.
I also went with two of the 32" LG 32UL950-W 4K monitors. I decided on these over the 5K LG's, as they look (in my opinion) much nicer with tiny bezels, and I prefer the screen real estate of the 32" display running at "looks like 3008x1692) over a 27" at "looks like 2560x1440" but with higher DPI.
These display are Thunderbolt 3, which means you can also daisy chain two of them together off of a single connection. I can confirm this works great connected directly to the mini.
I also purchased the Blackmagic eGPU Pro, which I know is overpriced, but it also has Thunderbolt 3. This setup works nicely with the Mini. I did not perform much testing (other than seeing it works) using the internal GPU.
Now, there are a few downsides. Occasionally, when I restore my mini from sleep (this happens maybe 1 in 20 times), one of the displays comes up at the wrong resolution. Going into display settings doesn't fix it, as it doesn't show the full array of display resolutions supported by the monitor. What does work is to just switch off both monitors, and switch them back on. A tad annoying, but not end of the world. Hopefully software fixes will eventually correct this.
Then, there's the well-known (and published by Apple) FileVault limitation. If you have an eGPU, you cannot see the login display to enter your FileVault password to unlock the machine. You therefore have to plug in your monitor to another port directly on the mini, log in, then plug it back into the eGPU after. Ugh!
I thought a solution might be to use the extra HDMI port on the back of one of the monitors directly to the Mac mini. Then, on boot, I can switch the mini over to HDMI, enter my password, boot up, and switch back to Thunderbolt.
This kind of works... however, the HDMI input of the monitor continues to be an active display within OS X (even though you can't see it, because you've switched to the other input).
There are utilities out there that would let me "disable" that HDMI display.
BUT, in the end I found that whole solution with input switching to just be annoying and have since disabled FileVault. It would be really nice if Apple can figure out how to make the minis firmware support the eGPU in some capacity to allow boot screens.
