Dentistry Interview Preparation Courses

For example, those run by Pass Dental, Ace medicine, Fast track Dentistry, med interview etc.
What are all these courses like? Are they really that useful and which one is the best - those who have been to multiple courses.

IMO I don't think you should go unless you can trust someone who has already been there and found it useful. Often these companies charge ridiculous amounts of money for just stating stuff you can find in books/websites. However, I recommend you have mock interviews with your school, or the career people or even dentistry students