Does what it's supposed to and well.

We use it to manage notifications for off-hours personnel when an incident arises. It automatically handles escalation if the primary contact does not respond. It was primarily used by operations but during our holiday office closure, we used to schedule and notify those on-call rotation personnel across the whole company.

I never experienced any downtime. It just works. Set and forget.

I have played with Slack integration. However, Slack is not officially adopted as a corporate standard.

For on-call off-hours support, clients can email a dedicated address or call and leave a voicemail at a special number. Either one will trigger a PD incident. An on-call person will triage. If they can resolve, then the incident is done. If the incident is more complex, then an incident lead will be notified and the Crash team will be activated. The incident lead will drive the issue until resolution.

I have not employed this feature as our incident counts are pretty low.