We've been running databases on ephemeral drives for many years, the key is using a database with good replication and failover. I don't think you should trust

We've been running databases on ephemeral drives for many years, the key is using a database with good replication and failover. I don't think you should trust your data to a single disk, whether or not it's a physical device in your own datacenter or an EBS in AWS. Everything fails eventually.