I have used (and liked) Transmit for OSX, although it is not free.
FileZilla—If you have more than one site, be sure to use the “Site Manager” feature. It will save you tons of time.
CrossFTP also works well, and it supports DreamObjects as well, which makes it doubly useful.
Also, AFAIK, pydio does not support SFTP, only FTP, which is a dealbreaker for me. SFTP all the way.