Forty five minutes on the roads the test actually uses, with an instructor who says only what an examiner would say, marked on a copy of the examiner's sheet.
It is deliberately not run by your own instructor. Somebody who has taught you for two months cannot mark you as a stranger would, and a mock test that tells you what you want to hear is worse than no mock test at all.
You keep the sheet and every mark on it is explained. Most people find two or three things they did not know they were doing.