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3rd.

Transmit is the best GUIfied FTP/SFTP client out there. Well worth the cash.
CyberDuck or Fugu are not up to par, but free.
 
Transmit

I'll give Transmit another boost. It's great.

If I have a huge file to upload Transmit is where it's at... Dreamweaver usually chokes on big stuff.
 
Transmit's actually the best FTP client I've used on any platform. Great interface, no problems. It's one of the few apps I actually paid for while a college student :)
 
In case anybody doing a forum search finds this thread and has the same question, here is a short review by Macworld of Captain FTP 4.2, Transmit 3.2, and Fetch 5.0.1.
 
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