I was looking for a quiz plugin and found this one. Good plugin and very simple to use. The UI is pretty simple and not too flashy. All features are good . They can do better by giving more customization options for showing answers. Like when showing all questions in single page, ability to show answer after user selects an option and presses a "show answer button".
One other feature that I would like to have is ability for logged in users to rate any question and then allowing the user to see questions based on their rating.
Overall, a very useful plugin. 5 star.