I did a comparison between Pagerduty and OpsGenie with the latter being like 1/10 the cost of Pagerduty.
There was no significant feature gap between the two and their sales team couldn't articulate one. At one point their sales guy told me they are positioning themselves as the luxury brand in the incident response market. Which ... yeah I'm cool going generic brand with my incident response tool.
As far as I'm concerned if you're a CFO you should be checking with your CTO or CIO to make sure you're not using Pagerduty. OpsGenie isn't perfect by any means but it's close enough while costings a fraction of what Pagerduty does.