So far I've only used them for the tutorial, but I definitely expect to start using cloud IDEs for real projects as well. They've really come of age in the last year or two. I suggest giving the recommended cloud IDE a try to see if it might meet your needs as well.
Thanks so much for replying! I am president of the Coding Club in my high school, and a lot of the rails teaching that I'm doing is based off of what I learned in your book. The school doesn't allow installing software on the computers, so using a Cloud IDE will be perfect for us. Thank you so much for writing such a great tutorial!