I’ve been using Xamarin University since april this year. My primary goal was to use it for certification purposes. The certification process requires you to follow several live classes where instructors go through the material using GoToMeeting. You can skip some of the required classes by taking an assessment exam.
When you have some experience with Xamarin, you can consider skipping some 100-level classes by taking an assessment exam. I went through all the required video’s for the assessment at a playback speed of 2x to glance through the material quickly. This gave me a solid idea about what level of knowledge would be required to pass the assessment exam.