When comparing Terminal.app vs Sublimerge, the Slant community recommends Sublimerge for most people. In the question“What are the best plugins for Sublime Text?” Sublimerge is ranked 26th while Terminal.app is ranked 27th.
Ranked in these QuestionsQuestion Ranking
Pro Default terminal on Mac
Since it is already installed by default, you don't need to worry about finding and installing another terminal.
Pro Great compatibility
Works with everything.
Pro Easily open man pages
By right clicking on a highlighted string you can easily search through the man pages for that string and the man page will open in a nice pop up window.
Pro Excellent xterm emulation support
Terminal has nice colors and font options.
Pro Light on System Resources
Terminal.app lighter uses less system resources than iTerm having the same number of windows, tabs and processes going on.
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 Updates are released rarely
Terminal usually gets an update when any new MacOS version is released, which is every couple of years.
Con Tab names are volatile
The tab names never stick -- it's imperative that this should work.
Con Background images are stretched rather than clipped
Con Occasionally crashes
Working remotely with a full buffer may cause complete terminal app crash.
Con Home and End keys require shift being pressed
Con Bad tech support
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.