Short answer is availability - we have three datacenters, and redundant connectivity around the globe. We have 12 of the Fortune 100 as customers for this reason.
Others:
Our phone and SMS alerts read the text of the alert to you, and you can ack/resolve/escalate right from there.
Centralized management of all alerting
If you lose a rack, we wake you up and tell you you have a thousand incidents, we don't page you a thousand times (and DoS your phone in the process)
Super-simple drag-and-drop scheduling
Easy multi-timezone rotations
Fantastic REST API
Happy to elaborate if you're interested - email is in profile.
Others: Our phone and SMS alerts read the text of the alert to you, and you can ack/resolve/escalate right from there. Centralized management of all alerting If you lose a rack, we wake you up and tell you you have a thousand incidents, we don't page you a thousand times (and DoS your phone in the process) Super-simple drag-and-drop scheduling Easy multi-timezone rotations Fantastic REST API
Happy to elaborate if you're interested - email is in profile.