When comparing SpaceFM vs Double Commander, the Slant community recommends Double Commander for most people. In the question“What are the best file managers for UNIX-like systems?” Double Commander is ranked 4th while SpaceFM is ranked 11th. The most important reason people chose Double Commander is:
You can use same tool in all desktop OS environments.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro Incredibly customizable
Just right click on any menu or menu option (including the context menu itself) and you'll be allowed to customize it. This lets you add support or integration for features you find missing.
Pro Minimal dependencies
It only needss gtk, udev, desktop-file-util and shared-mime-info which is available in most systems.
Pro Highly extensible
Functionalities can be extended by user scripts as plugins. Some scripts can also be downloaded from https://github.com/IgnorantGuru/spacefm-plugins/wiki. Plugins can be exported too.
Pro Tab and panel support
SpaceFM supports up to 4 individually customizable panels as well as multi-tabbed file management.
Pro No back seat driver
Does not obstruct professional work by engrossing root warnings.
Pro Desktop management support
Can be used to set wallpaper and desktop icons with high configuration support.
Pro Easily open folder as root
Can open different folders as root, this way you don't have to use the terminal to move around files for which you need root permission.
Pro Gtk-2 and 3 support
Available in gtk2 and gtk3.
Pro Intuitive and extendable through plug-ins
Great UI, easy to use and configure, several plug-ins available to make everyday tasks even easier.
Pro Multi-platform (Linux, Windows, MacOS X)
You can use same tool in all desktop OS environments.
Pro Source code is available (true free software)
If the developer loses interest there is at least the possibility that someone else will pick up the torch.
Pro Configurable
Lots of options allow you to configure DC the way it suits you best: Tools, Fonts, Colors, Hotkeys, Mouse, Fileviews, Plugins, Layout, Toolbars, Tabs, Icons etc.
Pro Directory Hotlist
Save shortcuts to folders. Organize them in a treeview with submenus. Define a name and sorting for each entry.
Pro Powerful tcmd-like search tool (alt+F7)
Pro tcmd-like multi-rename tool (CTRL+M)
Pro DC uses TCmd plugin API
so you can use documentation from Total Commander for writing plugins. WCX (packer), WDX (content), WFX (file system), WLX (lister).
Pro Closely follows TotalCommander UX
For instance, the 'Settings | Layout' pane is quasi-identical to TCs.
Pro Very sophisticated
Although it is lightweight and simple to use, it can do very sophisticated tasks, like copying files from directories which have a certain extension or file size or have a certain text pattern in them. Also, it's very customizable and stable.
Pro It's that good, you can replace tcmd on windows too
Pro Source code written in (Object) PASCAL
It's all a matter of perspective. I'm not for an argument about IDE's, frameworks etc, but to me that's a big plus. I think it should be a tie, it's either a pro or a con or should that be neither a pro nor a con. It just depends on context.
Cons
Con Ugly
Con Some operations are slow
Because it tries to be as lightweight as possible and tries to use very little RAM. This can unfortunately lead to it being slow sometimes.
Con Not for everyone
Con Ugly
Con Apparently only one developer
Con Freeze after mouse double-click on directory list item
Con Much slower on Linux and Mac than on Windows
Con Source code written in Pascal language
But this does not affect users negatively. It's just programmers problem.