I've used both Xming and Cygwin/X. However, for 64-bit Windows 7 and above, there really is one Open Source choice - VcXsrv Windows X Server
https://sourceforge.net/projects/vcxsrv
- It's an MS Windows X11 server based on the xorg git sources (like xming or cygwin's xwin)
- It is actively updated (at the time of this posting)
- It accounts for 64-bit Win7 & above and dropped the old XP cruft
- It's compiled with VC++ 2012 Express Edition, not 'mingw' (And also can be with VS2008, VS2008 Express Edition and VS2010 Express Edition - because they keep somewhat current/moving forward.)
- It includes all fonts and DPI that I'm aware of
- Properly supports multiple monitors - even with different orientations
BTW. If after install when trying to start VcXsrv you get the error below, it's because you're missing a MS Visual C++ Redistributable 2015. This isn't the only application with this error. Notepad++ and others have it too.
The program can't start because api-ms-win-crt-runtime-l1-1.0.dll is missing from your computer. Try reinstalling the program to fix this problem
Here's the fix (update, else get a MS download): http://blog.spreendigital.de/2015/09/01/how-to-fix-the-api-ms-win-crt-runtime-l1-1-0-dll-is-missing-error-for-delphi-10-seattle/