Version 4.0 of the Microsoft browser is recommended based on user feedback. Some difficulty may be experienced when using version 3.0. With my IBM-compatible PC running Windows 95 and version 4.0, it was only necessary to pop the CD into the machine and the CD was up and running. Using the program to find information and to move through its various sections proved to be simple and intuitive. There are some restrictions, so keep in mind that you are printing copyrighted material and treat it as such.
Some answers are obvious.
Reduced storage space as compared to the four printed volumes is one clear advantage. The ability to search for specific information and the speed at which information can be accessed are significant advantages. It is very convenient to be able to print information on the spot and not have to locate a copy machine. Some of the picture printouts are larger than those that appear in the book version - a nice fringe benefit. It would seem that the book versions will continue to serve a purpose for some time to come.