Moving away from SBS and going to 2008 R2 standard. Exchange Hosted now. Looking at hosting a secondary DC in the cloud with point to point ipsec vpn between the sites.
Secondary server will perform the following functions:
Backup DC, DNS (DFS File replication).
Users would access path \\domain.local\Share which points to both servers. Local server will be shortest path so would be accessed by users. In the event that server goes down users would still be able to access files at remote location. only 5 users in office. Files being accessed mainly Excel, Word, some jpegs...etc