When should we use Import rather than DirectQuery?

The data connectivity mode is chosen early on and is difficult to change later. It affects both how responsive the reports feel and how up to date the figures are.

Import

The data is loaded into the model and remains there until the next refresh. Reports are fast because everything is calculated locally, and the source system is only queried during refreshes. The trade-off is that the figures are only as current as the most recent data load.

DirectQuery

Every action in the report queries the source system directly. The figures are up to date, but the report becomes slower, and a busy source system experiences a noticeable additional load. In Dataverse, this means that report usage can affect those working in CRM.

The question you should ask

Will anyone make a different decision because the figure is ten minutes old rather than four hours old? The answer is almost always no. Choose Import unless you have a specific case where real-time data actually changes an action.