I'm currently in the midst of major revisions to the company website (168 files/folders in the remote directory, not counting subfolders/image files), and of the FTP clients I've accumulated over the years (Transmit, Forklift, Fetch, Yummy FTP, and Interarchy), Interarchy is the tool of choice for mirror operations. Why? While Transmit has great looks and features, it's *way* too slow in transfers/mirrors. Forklift is wicked fast, but the "Syclet" doesn't reliably pick up changes in local files as of the current version, v2.0.5. Mirrors are fast and reliable using Forklift itself, but I haven't found a way to get 1-click mirroring. Fetch is reliable, but does not offer a way to exclude files from mirror operations. Yummy FTP provides fast, accurate & flexible mirrors, but doesn't provide 1-click mirrors, although mirrors can be scheduled to execute automatically. I suppose if I wanted to mirror on a schedule, Yummy FTP would be just the ticket. The reason I use Interarchy is because I can start a mirror with 1 click in the menu bar and I'm done - no dialog boxes to click through. Interarchy never misses a revised/new file, so, for me, it's is the fastest, most reliable way I've found to mirror local and remote files.
Gripes: 1. No help (kind of a biggie), 2. Crashes more than it should in Cover Flow view, 3. Mirrors no longer can be scheduled as in v.9, "trial run" mirrors are not available as in v9, and 5. Nolobe, the developer, has not been responsive to my feedback and questions (sure would like to hear from that guy one of these days).
Bottom line: for web site maintenance these days, Interarchy's the best tool I have.