When comparing Kaleidoscope vs Sublime Merge, the Slant community recommends Sublime Merge for most people. In the question“What is the best tool for resolving conflicts when merging file changes?” Sublime Merge is ranked 9th while Kaleidoscope is ranked 10th. The most important reason people chose Sublime Merge is:
All actions are real Git actions which minimizes confusion and makes it perfect for beginners and professionals alike.
Specs
Ranked in these QuestionsQuestion Ranking
Pros

Pro Simple UI
Kaleidoscope has a beautiful and simple UI. It displays the two files that are being compared side to side, highlighting all the differences in a way that's easy to understand.
Pro Diff within a line
When working in code, line-by-line diff can still be hard to spot small changes within the line. Kaleidoscope will highlight what has changed.
Pro Supports comparing folders

Pro Image difference viewer
Kaleidoscope supports image diff viewer in addition to git diff. It's able to find even the slightest changes between two versions of the same image.
Pro Pure Git behind the scenes
All actions are real Git actions which minimizes confusion and makes it perfect for beginners and professionals alike.
Pro Speed
Nothing is faster. I used to use Gitkraken, but on large projects Gitkraken is barely usable.
Pro Very keyboard friendly
All actions have either direct hotkeys or corresponding entries in the palette (same as Sublime Text). This means a very streamlined and fast usage.
Pro No account info needed
No account- or server checkbacks (only for updates). All password handling is pure Git which means much less trouble and confusion.
Pro Portable version
Windows portable version.
Pro "Native" performance (Python based)
Very good performance.
Pro Using the trial version forever without limitations
Sublime Merge may be downloaded and evaluated for free, however, a license must be purchased for continued use. There is no enforced time limit for the evaluation.
Pro Lifetime testing
The product is paid but you can test for your life without paying (similar to sublime text).
Pro Excellent user interface
The user interface is designed excellently, and it's really fast to navigate with mouse or keyboard. It's never obscured which git commands are used, and commands can be modified/extended if desired. The visual appearance of the interface can be changed via themes, new git commands can be added, and even the menus can be extended.
Pro Not subscription based
A license gives you 3 years of updates, and you can use the product after that indefinitely.
Pro Bundled license available with Sublime Text (which is an amazing text editor)
Cons

Con Mac OS only
Kaleidoscope is a Mac OS X only app.
Con Paid software
Kaleidoscope is not free, costing $69.99.
Con Too expensive
And they're continuing to increase the price over the time, from the $60 that was at the start.
