The instructors always will give you good instruction, don't get me wrong, but plenty of people bust checkrides. The examiner doesn't care about your bonus. They care about making sure that person is a good and safe pilot. Everyone has some type of nerves before or during a checkride where they could make a stupid mistake and get a pinkslip, but that doesn't mean that they are a bad pilot. For the most part, all students go out of their way to excel no matter how they are paying for the program. Pinkslips are something that you try to keep off of your record. Plus, you are already paying the examiner at least $300.00, if you bust, you have to pay him more money to recheck. The people who don't take it seriously don't have the drive to complete, and would probably never make it in the industry anyway.