My dad is a professor who does part-time law practice. He had been using his university email address for professional correspondence, when he found out that the university had permanently lost 16 business-related emails in their spam filter (with no apology, notification, or compensation).

What I am looking for now is an email provider (preferably with Exchange, but not required) with very high reliability and a SLA that is basically an insurance policy.

I have looked at Google Apps's SLA, but this will not suit. I am looking for a provider who will take $X per month in registration fees, and will:

1. Alert me when there is any downtime.
2. Promptly fix the issue
3. Pay me a fee ($Y) whenever there is downtime.

I want a significant, contractual reason for them to be diligent in their service. Free service for me is not enough.