QOS term and policy of standard MX PLAN included in Hosting Pro

I'm aware that specialized mail solutions like "email pro" or "hosted exchange" have geographic redundancy, backup and 99.99% availability in their service specs, but I can't find this same information for the standard MX plans included with the hosting packages.

For example, I'm talking about the 100 5GB accounts included with the Hosting PRO plan. What are the data security and availability terms for these "basic" accounts? Can I expect the same treatment (physical and geographical redundancy, backups, etc) as the pro email plans or should I consider my data "at risk"?

I haven't found anything about it.