you will see with the time when you get used with it, you will learn to skip the Demo testing. Simply, your experience will show you which strategies you can test straight on live.
One of the interesting methods I showed in some of my courses is by removing the recent 1 month. In EA studio you have the option to set the Data horizon. For example if you are running the Reactor today on 1st oF December, you can set the end date to be 1st of Nov. After you select the strategies from the collection just as normal as you do it daily, you can change the date back to 1st of December. What you will do is just to remove the last one month from your Historical data, and than put it back.
This way you will see clear performance of the strategies for the last month, but instead of waiting one month you will do it for couple of minutes.
Of course in the courses I always teach the students to go first on Demo because this is the safer way.