Well, I've never used sftp through ssh, so I couldn't help you. And, I would guess that it is probably easier to just keep using ssh, so, no I would not recommend different software. Unless you're running a more high traffic file server, you probably don't need special server software.
If there is no one in this thread that has help for you, I noticed
this interesting, and unfortunately unanswered, thread on this site. It is a new thread though, so perhaps there will be some discussion on it.