When comparing Arcan vs KWin, the Slant community recommends Arcan for most people. In the question“What are the best Wayland compositors?” Arcan is ranked 5th while KWin is ranked 9th. The most important reason people chose Arcan is:
A pro- for programmers, but it is much easier to write a Window Manager for Arcan that it is for Xorg or any of the other options.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro Nice API for custom Window Managers
A pro- for programmers, but it is much easier to write a Window Manager for Arcan that it is for Xorg or any of the other options.
Pro Tons of features
So many things that can be done - video recording, streaming, clipboard managers, crash recovery, live window manager swapping, ... the list is endless.
Pro VR support
Pro Very customizable
Pro Integrated compositing manager
KWin has built-in compositing with options on how it performs that can be changed by the user in the settings.
Pro Highly configurable
KWin has a very configurable environment. Just about any option that you would like to adjust will be available in the settings.
Pro Beautiful interface
KWin has an assortment of attractive desktop effects, creating a rather beautiful interface.
Pro Window effects
KWin offers an assortment of window effects, such as wobbly windows and window shadows/glow.
Pro Can be configured to be similar enough to Windows so it makes life easier for fresh converts
While kwin is far more powerful, it can be configured to be similar enough to Windows - for people who just changed operating systems and don't really want to learn something new, it works great
Pro Offers desktop workflow
In an age where everyone seems to be moving to touch interfaces, KDE remains one of the last DEs that still caters for desktop users.
Pro Effortless VSync
VSyncing with NVIDIA blobs can be tricky (the dreaded tearing) but with KWin, video and OpenGL games display flawlessly.
Pro Readable code
Much better than any GObject based mess.
Cons
Con Difficult configuration
To work it requires configured Lua files, command line options, environment variables.
Con Dependent on some KDE libraries
This makes stand-alone KWin somewhat inconvenient to set up, as opposed to openbox and awesome, to name but a few.
Con Some effects are slow and jerky
Some of KWins effects (such as present windows) can be a bit slow or jerky, resulting in uneven fluidity. This is no longer true on modern versions.
Con Not really useful as standalone WM
No panel, no menu - just no way to start applications.