This plugin is much better than any other quiz plugin I've tried (and I'm pretty sure I've tried them all).
Initially, there's a lot to configure. However, you only have to do that once, and then you can export your settings to create new quizzes. Get used to importing/exporting a lot - it will save you loads of time.
I have a few minor complaints. Better default settings when creating quizzes would mean fewer mouse clicks. Also, keyboard entry could be speeded up (4 tab presses to jump to creating the next question, rather than just 1). And you have to jump between keyboard and mouse, which slows you down too.
Overall, though, this is a great quiz plugin which easily deserves 5 stars.