When comparing XtraFinder vs Transmit 4, the Slant community recommends Transmit 4 for most people. In the question“What are the best power user tools for macOS?” Transmit 4 is ranked 4th while XtraFinder is ranked 23rd. The most important reason people chose Transmit 4 is:
Exchange data with FTP, SFTP or WebDAV servers or your Amazon S3 storage.
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Pros
Pro Free
Pro Old full-size color labels from OS X < 10.9

Pro Adds useful toolbar items
XtraFinder provides useful options for toolbar such as: Launch as Root, New Terminal Here, New File..., and Select...
Pro Additional right-click options
Xtra Finder provides additional options when performing the right click.
Pro Custom hotkeys

Pro Copy Path

Pro Can open a terminal in set position
XtraFinder can open up a terminal from the right-click menu in given path with "New Terminal Here".
Pro Dual panel
Split the Finder window into to windows to achieve better file handling.
Pro Colored icons in the Finder sidebar
Pro Fast and powerful file exchange client
Exchange data with FTP, SFTP or WebDAV servers or your Amazon S3 storage.
Pro Supports Amazon S3 & WebDAV
In addition to FTP, allows exchanging data with SFTP or WebDAV servers or your Amazon S3 storage.
Pro Enable a server connection as a normal disk in your Finder
So you can access your storage without the Transmit client.
Pro FTP Sync
Scans local and remote for difference and only transfer modified files. It's not rsync, but it's the next best thing
Pro Can enable a server connection as a normal disk in your Finder
So you can access your storage without the Transmit client.
Cons

Con Doesn't work on recent macOS versions without a workaround
This tool doesn't work on recent macOS versions, except if you try workaraound that may or may not work. It involves disabling System Integrity Protection and details on how to do it can be found on the XtraFinder website.
