A quick update to provide another data point.
I recently replaced two UniFi AP AC Pros (wired uplink) and an AC Mesh (wireless uplink) with two Ruckus R710s (wired uplink) and a R510 (wireless/mesh uplink), running the Unleashed firmware, and have been happy with the results. It has only been a week or two, but performance and reliability appear to be just as good, if not better, than the UniFi setup; distribution and roaming across access points appears to be vastly improved as well. The Unleashed management web UI is much simpler than the UniFi setup, as it's not burdened with managing your entire network, but I found it to be easy to use with quick access to everything I needed to tweak/view.
The one catch worth mentioning is to pay close attention to which Ruckus access points support mesh networking as not all do. I originally picked up a R310 to use as a wireless uplink for a disconnected wired network only to find out that it didn't support a wireless/mesh uplink; it was clearly stated in the specs, I just mistakenly assumed all of the Unleashed access points supported this feature.