When comparing GNU Diffutils (diff) vs Sublimerge, the Slant community recommends Sublimerge for most people. In the question“What are the best Linux diff tools?” Sublimerge is ranked 6th while GNU Diffutils (diff) is ranked 8th.
Ranked in these QuestionsQuestion Ranking
Pro Command Line Interface makes it easy to use for people who work a lot in the terminal
Great for creating patch files, using with other *nix utilities (for example, colordiff). Does not require a GUI.
Pro Creates patches
These patches can be used to apply the differences to the same source file at a different storage location (different folder, different machine).
Pro Multiple formats
The difference can be output in formats known as normal, unified, ed, rcs, and side-by-side.
Pro Compares entiry directory trees
Two directory trees can be compared file by file recursively. All differences are output concisely.
Pro Three-way diff allows easy merging of files
i recommend Sublimerge
Pro Highlights intraline changes
Pro Built-in support for Git, Subversion and Mercurial commands
Sublimerge automatically integrates with your version control history, and lets you compare between revisions, branches, remotes, and the staging area.
Pro Can compare to clipboard contents
Con It's NOT Open Source
You can't fix or, implement nothing. And when the developer abandons the project you will be left in the lurch.
Con It's not free
Nither as free price nor as free in freedom.
Con Cannot compare text within the same file
Sublimerge can only compare entire file diffs, but not two selections within a file. Comparing within files can be useful for example, by refactoring two similar functions to use a shared function. With Sublimerge, you need to copy the sections into two new temporary tabs and compare between the two. This can be cumbersome, as if you have another untitled file, you won't be able to know which one is which.