Any good multi-threaded SFTP clients for Mac? I am amazed that there doesn't seem to be a decent multiple connection capable FTP/SFTP client for Mac.

The only one I've seen is CaptainFTP, which looks awful, like it's from the last century.

There's also iGetter, which is equally ancient, and not really set up as a browser, more of a download accelerator.

I've been using lftp, which is amazing, but CLI only, which makes it a pain.

Does anyone know of either (a) a "modern" client app which supports multiple connections, or (b) a GUI for lftp?
Old question, but I found that Cyberduck supports multiple connections. When transferring over SFTP, it's possible to select multiple connections in the upper-right of the progress dialog. Whether that has an effect on the total speed, I am currently not able to measure.