I can't speak for the other schools, but I can speak for Berkleemusic (which is the online version of Berklee College of Music). I've been a student for 1 year and enrolled in one of the Master programs. The course content is excellent and the professors are very knowledge, talented and helpful. Each student's experience depends on what they put in it.
Now, for me it took some getting used to having online courses. I'm used to classrooms with my professors and classmates face to face. Having chats as the main interaction is still a bit strange, but it leaves the opportunity to learn a great deal. Sometimes I'm the only person in a chat with my professor for an entire hour. It's like having a personal tutor!!! All chats and content are available for 1 year after you finish the course.
I've adapted to this manner of learning and I'm sure any person who has learned anything from the internet would be able to also.