There was one product that came to the front in almost every test, so we have no hesitation in declaring Panic Inc's Transmit our choice for the FTP Group Test winner.
Transmit shows that the combination of elegant form and useful function can lift a product head and shoulders above its competition.
It isn't perfect; it would be wonderful to have syntax-coloured text in its internal text editor, for example, and it didn't fare that well on the basic file transfer speed test because it processes the items within a single upload request sequentially.
However, it's a well-honed tool that is designed to work in a pleasing, as well as efficient, manner. Add to this the Dashboard client (also offered by Captain FTP, Fetch and Cyberduck), the Docksend ability (drop a file onto the dock icon for predefined uploading to one or more locations), and the droplet creation support and you have an app that is designed to work hard.
Of course, many of the other products on test are worth considering, but most will agree that Transmit is king of the FTP world.