Actually for me, this is much more important: "Symbol and definition lookup is another great feature of WebStorm. While Emacs can find symbols and definitions in a single file via Tern, WebStorm can actually inspect your whole project and find a definition, or at least give you a very pruned list of candidates to choose from."

not being able to Ctrl-click a variable or function really reduces my efficency (especially with code that I did not write entirely on my own).