When comparing Komodo IDE vs RubyMine, the Slant community recommends RubyMine for most people. In the question“What are the best Ruby IDEs?” RubyMine is ranked 1st while Komodo IDE is ranked 5th.
Ranked in these QuestionsQuestion Ranking
Pro Built in Version Control
Since Version Control features are very frequently used these days, having them built right into your IDE seems quite the right thing to do. With Komodo, you can perform your Git push-es and pull-s right while you're coding.
Pro Collaboration tools
If you're working with a remote dev team, you'll quickly realize the importance of code collaboration while programming. With the Komodo IDE you don't have to setup a separate teamviewer session, or even share code via dropbox with other devs. All you need is an ActiveState account (+ a partner with the KomodoIDE ofcourse) and your remote team could see LIVE and contribute to your changes in the source files of your app
Pro Great code completion
Pro Lots of keyboard shortcuts
Pro Great git interface
Has a built-in git client.
Pro Excellent database support
Supports a wide variety of databases. Even MsSQL and Mongo.
Pro Very good extensibility
The IDEA/RubyMine ecosystem provides a lot of plugins.
Pro Intelligent Code Navigation feaatures
Single keystroke to code for an object, find uses of object code, rails model-controller-view, and more.
Pro Great automated testing integration
Configure it to use whatever is your preferred test framework and easily run all tests from directory or file or individual tests, with run buttons in the margin. Test outputs link directly to the lines of code you need to work on.
Pro IdeaVIM plugin adds Vim-like bindings
IdeaVIM plugin is available here.
Con Not free
Komodo IDE costs you $89 for a personal license. Even though they have a Free basic version (that's also opensource), but this lacks most of the functionality that the paid version has.
Con Sometimes slow
On large projects, performance can be an issue
The price tag makes this unattractive for learners or hobbyists.
Con Constantly Indexing on large projects (even after invalidating caches)
I love this product and have been a supporter for 4 years, but performance on large projects is now a deal breaker :(