Which version should you use?
That is a question with only biased answers.
There is only one which can answer really YOU!
Why is that?
The real choice is the workspace - the desktop environment.
Why all the choices then?
What really differentiates the choice of environment, is how it is put together.
We all have different workflows, different taste, different hardware, different requirements.
Some prefer eye-candy while other prefer a workhorse and some is deeply accustomed to a specific layout of the screen like where the Start button (Windows users) is located, how the menu system is displayed/organized etc.
Eye candy versions like Gnome and KDE often get updates and tend to have more issues than older and more stable versions like Xfce or pure Window Managers.
Windows users might like the Xfce desktop or even the KDE best as they offer a certain familarity in the layout of the application menu and taskbar.
But as said - you are the only one to decide - and it is your taste, your data, your computer - it is all about you and not us.
We cannot tell you which desktop layout is right for you.
How do you decide then?
First glance using live sessions
Safe installation using VirtualBox
A safe installation of Manjaro can be done using use VirtualBox. You can install the downloaded edition as a virtual computer.
A virtual computer is a safe way to try how the different environments behave on a longer term and if they appeal to you in either way.
Such a virtual computer comes with absolutely no risk to your current environment. It requires only disk space. You can create as many virtual machines as your available disk space allows you.
Create a virtual computer for diving into the world of Manjaro and assign it
- two cpu's
- at least 2GiB RAM
- 16 GiB virtual harddisk
Some hints from @Chrysostomus
If you don’t know what you want
- Start with Xfce. Try next KDE or Mate.
If you like Windows
- Try Xfce, KDE, Mate, LXDE or LXQt.
If you like mobile devices
- Try Gnome and KDE.
Those have the best integration with phones. Gnome UI feels familiar to smartphone users and KDE has decent touch screen support.
If you like online integration
- Try Gnome. Maybe KDE.
If you like using the keyboard
- Try Gnome, Awesome, i3, Openbox or bspwm.
If you are open minded
Requires patience and willingnes to try something very different
- Try Awesome, i3, Openbox or bspwm.
If your computer is really slow (Windows XP era or before)
Manjaro has no official support for 32-bit systems. 32-bit community support is provided by two very small teams. Manjaro 32
- Try LXDE, LXQt, i3, Awesome or bspwm.
If your machine runs Windows, chances are that it runs almost any Linux desktop just fine. Except maybe Gnome and its derivatives (Budgie, Cinnamon, Deepin).
If you like eye candy and effects
- Try Gnome, KDE, Deepin, Cinnamon or Budgie.
If you want things to just work
- Try Xfce, KDE, Mate or Gnome.
If you like tinkering and tweaking
- Try Xfce, Openbox, Awesome, i3 or bspwm.