(xdg-open seems to be supposed to be the universal one...)

xdg-open should do the same thing - actually, it will call gnome-open, or kde-open, or whatever, depending on your desktop environment. Thus it's more portable.

The advantage is that you can use gnome-open for almost all file-types, URIs and directories. It's one command to learn, instead of trying to remember about obscure commands like sensible-browser