Ask HN: What is your experience with Parse's BAAS in production?

Hello HN'ers,

I am about to launch an app that is using Parse's backend and Notifications service. I am interested in knowing your experience with Parse. Do you have any app/website in production that uses Parse's services? What is your experience from stability perspective and Cost perspective? Any surprises? Have you moved (or thinking of moving) away from Parse for any reason? Please share.