I use exe book for about a year now. I like it and I sell about 8-10 books a month. I like it because it has options that keep people from passing it to other computers for free. The pages turn just like a book. you can design your own cover. there are some drawbacks like lack of support. But, I never needed any with this book.  If you listen to people that say they won't load programs into thier computers. you will never sell a book. And besides, if you have a following, they will come to buy from you. Viruses? give me a break. Who in their right mind would sell an E-book with a virus. Might as well say don't download anything from anyone, anywhere. other than that there are slide show programs that work just as well, with features built in to not let your work be passes from one computer to another for free.