Deluge runs on it's own in Python-GTK, while rutorrent requires an http daemon to work. The torrents that you have right now will still run in the rtorrent console (if the seedbox provider allows it), but you won't be able to get to access to them through the rutorrent interface. If you don't have access to SSH, it would be beneficial to cancel the ones you have running right now before making the change to Deluge.