For years, I've used Filezilla; first on Windows, then (and currently) on Mac OS. Always been happy with the interface: I don't need pretty, I need function. My complaint is this latest update (3.9.0.1) has changed some functions I've grown used to. For example, I usually minimize the app using the default Mac OS keyboard shortcut, Command-M, but now this brings up the manual transfer window. Visiting the Filezilla forums yields comments from the developers like, "be glad we even offer a Mac version". Hmm, and it just crashed as I am writing this.