Well, as I am in the last semester in my grad program, I can honestly say I had no interest in e-books for my texts, or renting textbooks. It's mostly because I have to study for licensing boards sometime in the next 2 years, and I want to use my texts for some of that. I also want the books to refer to at times, for what I do in my daily practice. It's hard to explain, but I need to "feel" the book.
Of course, I am old and old fashioned when it comes to electronic books. I even print out the research articles I use, because I like to mark them up and highlight, especially when I am using an article for my own research. While I appreciate being able to access the articles/library on line, at home, I want the articles.
It really comes down to your learning style. If you think you can study, memorize, take notes by looking at a screen, and it's cheaper and easier, then do it. I couldn't. You might want to buy some of your clinical books, later on, though, for boards and the diagrams as you said.