Until version 10.8.4, you could use "PC Quick Connect" to connect to multiple RDP serssions.Starting with version 10.9.0, if you use "PC Quick Connect" to establish an RDP session, and then try to establish a new session, you current session disappears as soon as the "Enter Your User Account" dialog is displayed.
This behavior does not happen when you establish a session using a saved Device.
When you are managing large numbers of Windows systems, it is not desirable to have to save connections for every one of them.
It would be great if "PC Quick Connect" could regain the ability to establish multiple concurrent sessions.