When comparing SpaceFM vs Krusader, the Slant community recommends Krusader for most people. In the question“What are the best Linux file managers?” Krusader is ranked 7th while SpaceFM is ranked 9th.
Ranked in these QuestionsQuestion Ranking
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 Tab and panel support
SpaceFM supports up to 4 individually customizable panels as well as multi-tabbed file management.
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 Desktop management support
Can be used to set wallpaper and desktop icons with high configuration support.
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 Gtk-2 and 3 support
Available in gtk2 and gtk3
Pro Minimal dependencies
It only needss gtk, udev, desktop-file-util and shared-mime-info which is available in most systems.
Pro Great two-pane interface
Pro Folder synchronization
Pro Virtual file systems
Search results as example saved into virtual folder and can be accessed later. All file operations may be performed on items in search results as if they were files in single folder.
Pro SFTP support
Pro Handles most archives. There is little difference in behaviour between an archive file and a regular folder.
Pro Searching capabilities and copying/deleting/moving in background
Pro All common operations can be done with keyboard efficiently
In addition, shortcuts can be easily renamed.
Unlike Dolphin and many others.
Pro Many operations like copying and moving files can be queued
Long running operations can be queued.
There is no point in doing them in a parallel way, as speed decreases dramatically.
Pro Can view and edit many files
Even editing a file inside a .zip file.
Has hexadecimal viewer embedded for binary files.
Pro Filename association and instant console availability
Pro Multi-rename tool
Pro Custom commands can be added to the menu easily
And they can use the current folder, the selected files....
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 KDE dependencies
If you don't use KDE, you'll be forced to install quite a large amount of KDE libraries.
Con Interface can be overwhelming
Con New releases are infrequent
It can be seen in https://quickgit.kde.org/?p=krusader.git that maintenance work is done in a continous fashion, but no new releases are provided.
Even though it is perhaps the more feature-rich file manager.