Azure Scheduler seems to be aimed towards recurring tasks. So a scheduled request from Posthook is more actionable than a recurring execution from Azure Scheduler for the use cases I'm aiming to help solve with Posthook (think reminders). Also I'm hoping Posthook is a simpler offering in terms of pricing and integration.
The Azure service also supports logging (60 days), retry options, and advanced recurrence schedules (every other Tue, etc.)?