The Test (Test.Org) environment is the perfect testing environment available from everywhere in the world.
You can deploy as many applications as you and just test them.
The testing environment is allways available and speed up your Development<->Testing cycle by just giving you the opportunity to have your people testing the application as if they where in the production environment, but having access to the last functionality you just developped.
You can make your business people participate in all phases of your development, and adapt the application to the most detailed specifications and requirements.