Last month I recorded my first real gig using the Steinberg UR824 and a Behringer BCF2000 with ardour3 under Linux, and it was perfect. Glitch free as far as I can tell, and the functionality was just as I needed.
The picture shows the ardour3 mixer, with one of its PFL buttons proudly illuminated. Why proud? Because this wass one of the wonders of going the Linux route, I was able to get true PFL functionality and modify the setup so it worked exactly as I wished when I pressed the buttons on the BCF2000 control surface.
Now of course nothing in the open source world is guaranteed, but if you'd like to try it, I've uploaded a new version of the driver to the installation page. I've also uploaded a new ur824ctl tool, that allows you to control the routing inside the UR824 in a top-down kind of way. All comments/encouragements gratefully received at firstname.lastname@example.org