You mean the new Elastix, that’s now 3cx?
I would say there are pros and cons to both.
In Freepbx you can pretty much do anything. If there is a feature you desire and Freepbx doesn’t support it right or of the box you can write it yourself with some knowledge about Asterisk dial plan scripting. In 3cx you are stuck with what they give you.
Biggest pro for 3cx imo are their built in soft clients for mobile phones. They’re very useful, free and much more convenient to setup than anything you could do on Freepbx with 3 party software.