I was very impressed with Cornerstones documentation. They have a plethora of guides to virtually allow you to set up your environment without much assistance from the application specialists or customer relations manager.
Based on my experience with Cornerstone they have an empowerment strategy that is welcomed by me. They help you to be empowered to do virtually every task within the system limits that you would need in your everyday course of business, unlike other systems where you would have to call for each administrative or system configuration change. This is not the case with Cornerstone.
Great for an organization just starting a Self Service option for performance management. Easy to navigate and setup Roles and Administrstion. Please take your time with implementation in order to test all case senerios.