Review of RubyMine powered by the Slant community.
Ranked in these QuestionsQuestion Ranking
Pro Great code completion
Pro Great git interface
Pro Excellent database support
Supports a wide variety of databases. Even MsSQL and Mongo.
Pro IdeaVIM plugin adds Vim-like bindings
Pro Very good extensibility
The IDEA/RubyMine ecosystem provides a lot of plugins.
The price tag makes this unattractive for learners or hobbyists.