This was a failover, not a restore. And we were just lucky that the failover machines (in the same datacenter) were not affected.
Do you think you will change hosts and/or have secondary services elsewhere?
Why not spin up some EC2 instances if your main datacenter fails? You can pay minimal costs to send a diff of your database a couple times a day in order to keep the backup current, and only pay for real bandwidth if your main server goes down. Seems to be a pretty decent backup plan.