Are online text books more helpful than printed textbooks?
This question must be taken on a case by case basis. For instance, when there is both a printed version and an on-line version available, then this question doesn't really make sense.
In some cases, a digital textbook can provide functionality a printed version cannot. When this isn't the case, we should be able to create a PDF from the digital version. If we don't have the permission to create that PDF ourselves, and the publisher will not, then we run into some problems.
On Textbook Revolution, we encourage people to seek out downloadable-versions of books. We provide a field for both URL and Download link -- where often the URL is the web site of the book or main download page of a particular author, and the Download link is the URL of a PDF version.
A: Yes and no. Yes, if you have a technical book the PDF version could be easier to navigate. And no because reading Shakespeare on a screen for me is too hard on the eyes.