Are IsPresent() and WaitUntilExists() interchangeable?

WaitUntilExists and IsPresent are not interchangeable. WaitUntilExists can be used to synchronize with the target application where as IsPresent can not. When a test calls WaitUntilExists, AscentialTest takes snapshots on an interval until the timeout period elapses to determine whether there is a change in the state of the target application. IsPresent operates on the most recent snapshot. While WaitUntilExists can be called for top level windows and application controls, IsPresent should never be called on a top level window.