In the golden age of FTP there are plenty of great proprietary clients. Of of my mind I can think of (for Windows) FlashFXP, FTPRush, CuteFTP, SmartFTP, and so on.
Transmit is good too, although I really liked the Scheduling function YummyFTP had. It was great for setting a large download to 2AM when the DSL network wasn't overloaded. Wish Transmit would add that feature. I suppose it can be done with Automator but it's not as nice as built in.
