When comparing XtraFinder vs ForkLift 3, the Slant community recommends ForkLift 3 for most people. In the question“What are the best Mac file managers?” ForkLift 3 is ranked 5th while XtraFinder is ranked 10th. The most important reason people chose ForkLift 3 is:
It's just a perfectly crafted app, try and enjoy
Specs
Ranked in these QuestionsQuestion Ranking
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 Best UX/UI'd file manager on the market
It's just a perfectly crafted app, try and enjoy
Pro Rewritten in Swift
Forklift 3 is a significant update from FL2, having been rewritten entirely in Swift.
Pro Optional dark UI
In addition to the default Mac gray UI, Forklift 3 offers an alternate "Dark Mode" featuring light text elements against dark backgrounds.
Pro Connect to and mount lots of storage options
FTP, WebDAV, Amazon S3, Backblaze B2, Google Drive, Rackspace CloudFiles, SMB, AFP, NFS, VNC, etc.
Pro Easily toggle hidden files
Pro Built-in application remover
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.
Con Like Apple, it does not standardize file size. Mixes up KBs, MBs GBs in the same column which makes it very difficult to review file sizes
Con Like Apple, shows the date of Today's file as "Today" instead of the actual date
Con Does not sync the "selected" folders (i.e. highlighted ones), but the "current" folders (i.e. the top of the visible tree.)
Con Does not show the fixed tree section in the left pane of a dual horizontal panes
