It's easy (and expensive) to make professional looking animation
GoAnimate is expensive, and even the 'for education' accounts are not cheap. I like that it is easy to use; students didn't have any problems figuring it out. If I were in charge of budget, I don't know if I would approve the cost for this tool. It is fun and creative, but doesn't really add to students' learning that much. They could show the same learning by creating a storyboard, for example. They could use Voki as well, although they could only have one character speaking at a time.
How I Use It
I used GoAnimate in a variety of ways. I have created animations to show in class to teach students about a topic. In U.S. History, my students were learning about conservatives and liberals. I created a video in GoAnimate that was a conversation between two characters discussing the role of government. One of them showed a view consistent with liberals, and the other with conservatives. After reading their textbook and learning about these two groups, I had students choose a different topic such as welfare, healthcare, education, etc. They worked in groups to create a conversation and then created a video in GoAnimate with one character showing the conservative view and the other a liberal view.
My students enjoyed using this tool, but they did say it was time consuming. There are so many choices--from templates, to characters, music, props, etc.--that students sometimes got 'lost' in this and didn't spend as much time on the content. I would be sure to have them write out their content/conversation first before allowing them to create their video.