If you are a one man show and strictly a Microsoft shop, then SourceGear Vault is definitely a prime candidate for switching too.
Features:
- Free for Single User, great for you
- It uses SQL Server for it's backend, therefore data reliability is huge
- It has atomic check-ins, all files checked-in at the same time are arranged in a group and are called a changeset.
- VisualStudio integration.
- Has a tool for importing from SourceSafe, therefore you can keep your history
- The client communicates with the server over HTTP, therefore accessing the source outside the office remotely can be setup very easily and performs well, because they only transfer the deltas of the changes being submitted and received. You can use SSL to secure the connection.
I would definately consider this as an option.