I use this program with my students because it comes pre-loaded on their school-required IBM laptops. I was very excited a few years back to start using it because it allowed me to drop the anthology text from my required texts for the course, thus saving the students quite a bit of money. My tech coordinator also was happy that families could see yet another way the laptop "paid for itself."
Then came the glitches. For example, there are no line numbers ... on anything. Try reading and discussing Hamlet with your students and not being able to reference a certain spot in the text. Then I learned that the translations provided were (this should have been obvious, but I still had to learn it ...) the "open" translations. That is, the ones that are not copyrighted. That is, often the ones that are not as good. So for my world lit students, the Bhagavad Gita translation was nearly impossible to understand.
So here I am a few years into this. My students still read a few things using VitalSource, but I have found on-line texts to download (and properly cite, so no worries there) into Word or Google docs for as much as I can. This allows me to add line numbers at the very minimum.
All of this just makes me think about the stops and starts that come with trying to use technology as a tool in the classroom. No wonder many people don't ... who has the time to discover that a seemingly easy transition to laptop texts ends up being fraught with problems? Obviously I do ... sometimes. But I don't other times, and that is the constant struggle. I want to learn and be a better teacher, but sometimes I just have to do what I have always done and trust that it is okay too.