I use PhpStorm remotely and on-site. I currently have the project downloaded at both locations and sync with the deployed server. I learned, however, that PhpStorm has the
If I edit files directly on the deployed server, would any PhpStorm functionality be lost?
Yes. To name a few:
Remote-only editing can be practical only if you need to make some quick changes (e.g. fix typo; change some config value) or where no cross-referencing is required (e.g. you know for sure that file with such name exists at that location; or class has such method with those parameters etc). With the same success you can replace PhpStorm IDE with much faster Notepad++/Sublime or any other text editor with FTP/SFTP support.