The benefit of open source is really better plugins. It's much easier to create plugins for an editor if you can see the editor's source code. This is true for

The benefit of open source is really better plugins. It's much easier to create plugins for an editor if you can see the editor's source code. This is true for IntelliJ IDEA and Atom in particular. I have been able to create pretty great UIs and other features in IntelliJ plugins from looking at and introspecting the IntelliJ code to see how it was done there. The other benefit is that if the company dies you know you wont have wasted all that effort with the editor because open source editors don't live and die at the behest of the company that started them.