This book, "Testament," is good for showing more of his unpublished stuff. It has many Playboy-type girlie paintings and drawings, some western themes, and his paintings for TV Guide, for the "Battlestar Galactica" show, (which look nothing like the actual TV program, but stand as terrific space fantasy works). The personal photos are also a very nice insight into his life.
All three books in this trilogy cover work from his whole life, and explain his career moves, with slight variations and different guest commentary. The printing is nicely done, so you can enjoy studying the paintings on glossy, quality paper. These three books are very nice additions to your personal bookshelf library.
If you're new to Frazetta's work, I would just suggest that you start in order, with "Icon," and then "Legacy," where the more popular works are printed, to be able to appreciate and understand Frazetta's work and influence in proper perspective. "Testament" is more for the confirmed Frazetta fans.