Server hosting for enterprise email hosting?

Our company is evaluating dedicated server providers for enterprise email hosting.
Security, compliance features, and 24/7 support are essential. Which vendors have proven track records in this field?
What can you say about Greenwebpage.com server hosting reliability?

I will be migrating all my current customers, their sites, hosting and domains to Greenwebpage.com next week.
The site speed is good. The servers are secure. The prices are fair. Everything is clearly organized for a great user experience.