When comparing krusader vs nnn, the Slant community recommends nnn for most people. In the question“What are the best Linux file managers?” nnn is ranked 1st while krusader is ranked 20th.
Ranked in these QuestionsQuestion Ranking
Has everything you might wish for and more.
Pro Root mode
Dangerous but sometimes useful.
Pro Multiple tabs
Tabs with other listings, and options to move the tab to the other side.
Pro Advanced renamer
Via package krename.
Pro Directory compare
Compare 2 directories on content or file/date and sync them.
Pro Archive support
Browse archives as folders.
Pro Extremely lightweight (120 kb)
Pro Rich set of plugins
Pro Has a great wiki
Save and resume sessions.
Pro Minimal configuration with sane defaults
Default options and navigation is simple to grasp.
Pro Unique navigate-as-you-type mode
Pro Supports cd-on-quit
Allows for quick switching between nnn and the terminal.
Pro Awesome new features being added in every release
The file manager has recently added support for preview hovered files using various methods.
Pro Integrates with the desktop environment and opens files in the default applications
Pro Reasonably well-documented
However, it requires some prior knowledge of inner workings of Linux and there are no tutorials (yet). NNN author is making up for this by actively responding to GitHub issues.