PHPstorm was excellent when I, a Ruby developer (among other languages), had to adopt a PHP codebase. RubyMine was less impressive, especially with all the enhancements available for Pry and IRB. RubyMine couldn't find method declarations or infer types the way PHPstorm could.

So, I stick with Vim for Ruby, but don't rule out IDEs entirely for other dynamic languages in a pinch.