IM working there now.
Take my advice. Don't work there. It is the worst job I have ever had and I can't wait to get out - the "rumours" are true to an extent. Its dehumanising, repetitive. You are basically expected to run around for 10 hours.
The whole place runs on the idea that managers are "better than you" as a person and you have no rights other than those gaven to you by the law. Its awful. It may take a while, but look somewhere else.
If you must know though...
The On the Job Experience was basically me walking around "interacting" fakely with the cattle...err, I mean customers, cleaning some tables and thats it. Some times your on tills for 10 mins or less or something instead.
The interview is an easy joke.
Just dont do it.