I use both on a daily basis. Sublime is incredibly fast, and I constantly find myself switching from Atom to Sublime for various reasons (big files to edit or big JSONs to format, search and replace across a big project...). Atom's UI is really great though, I wish Sublime came close as for the user-friendliness of the configuration. Also Atom now has better plugins than Sublime.

Note I also use VS Code a lot because its Git Diff view is awesome and its debugger is a rock too. The extensions are generally not great though.

And I use vim when I need to edit a single file quickly.