At this moment in time that maybe true but just wait for the next version of Firefox and I am sure that IE will have nothing over it. Except it will still be the one basic computer users use cos it is what will come on their new computers with Windows Vista.
I am sure that firefox can get better than IE7, now they need to add 'save the last session' feature for multi tabs, I love this feature of Opera and now it available in IE7 too. just not in Firefox.
Yes, WS_FTP is best FTP program for Download and Upload (Support resume #1). However if you want to delete a directory it must be empty - in this case use another FTP program such as FileZilla to Delete If you want to backup file from server to your PC why not ZIP all files in server and use download zip file to PC and delete after download. It is quick. If you use cPanel you can zip file in File Manager.
filezilla is awesome. use it every day to transfer files to my site. maybe it's in your settings, mate.