It's working reliably for the company I work at, sending out around 300 (total) GCM and APNS pushes to subscribers per second. (Across 3 servers, which is probably overprovisioned)
- Redis DB locking was disabled
We're using the latest uniqush-push. It's working, and is stable without the need for manual intervention in the last year. An old blog post documenting how we set up uniqush-push at our company can be found at
https://misha.nasledov.com/uniqush.html
There is an infrequent issue with sending duplicate push notifications to GCM users if the app gets reinstalled (They can end up with duplicate reg ids. This can be worked around if device ids get tracked, but that isn't implemented yet)