Powershell Restore Azure SQL Database to local with Restore-Database

I have written a powershell script that uses Start-AzureSqlDatabaseExport & Get-AzureStorageBlob to export my azure DB to a bacpac and download it locally, the next step is to restore the bacpac to my local SQL DB using Restore-Database, but below fails with "the media family on device is incorrectly formatted".

Restore-Database -dbName "MyDB" -backupFile "C:\MyAzureBackup.bacpac"

Is there a way to get this working with Restore-Database, or is there an alternative command that will do this?