I've been self-hosting Postgres for production apps for about 6 years now. The "3 AM database emergency" fear is vastly overblown in my experience.

In reality, most database issues are slow queries or connection pool exhaustion - things that happen during business hours when you're actively developing. The actual database process itself just runs. I've had more AWS outages wake me up than Postgres crashes.

The cost savings are real, but the bigger win for me is having complete visibility. When something does go wrong, I can SSH in and see exactly what's happening. With RDS you're often stuck waiting for support while your users are affected.

That said, you do need solid backups and monitoring from day one. pgBackRest and pgBouncer are your friends.