The ease of use and simplicity of the interface are my top "pros. It was also relatively easy to set up from an administrative standpoint and integrates well with other NetSupport products.
The ease of use is what drew us to the notify. When you start up notify you select the options you'd like type your message and select the computers you want to receive it and off it goes.
The control you have... just overall. It's awesome to be able to see everyone's screen, lock down certain things, push things to them, etc.
Instead of calling around to each department, we can now send a message out when we are going to conduct a fire drill or restart a server.
No working/notification of message character limit - we have created messages and sent them to then only see that the entire message is not displayed.
Sometimes the updates make things difficult. We have had to use work arounds in the past until the developers pushed out and update to fix them.