My Take
I have used this as a way to present information and for students to present. Overall it is a decent teaching tool. It does have some short comings. I really think it depends on what your purpose is for your presentation. If you want the students to really go in depth on a topic and add animations than PowerPoint would work better. However, if you are looking for a simplistic way to have students present information than Sway would work. Sway can be used for more complex presentations, but it lacks the editing skills that other presentation tools have. It is a great starting tool for students to use to learn how to present.
How I Use It
I have used SWAY as a presentation tool for my students to explain a Science concept. SWAY does have a collaboration piece to it, but we have not used it lately. The students were not given any directions on how to use the application. I wanted them to figure it out based on their knowledge of other applications. They were able to easily figure out how to use SWAY and create a presentation on it. The students were able to use most of the features with ease. There were some issues with trying to group images and the biggest complaint from the students is that it didn't have enough editing tools to do more. I have used it with a 5th grade class.