I think it would be nice, if it would be possible to disable access to an FTP user if they come from a wrong IP address.
In our scenario we have multiple clients of ours coming for files. Now we allow any of them to come from any IP address, because some of our clients don't have fixed IP addresses. And in order to start using IP filtering, I need to set IP filters with IP addresses of all users.
However, it would be nice, if I could set IP filtering not per site, but per user. Client opens our ftp, enters user name, and gets refused right away (maybe even without having a chance to try his password) with a custom message, because he's not coming from the IP address that we have signed in the agreement.
I know that it would be possible to setup multiple sites in CompleteFTP Enterprise, but then I would need a separate site for every client, which is administrative overhead.