Re: the Purvis translation -- with a plethora of annotations, diagrams, maps and complementary essays, I can't think of a better way to absorb this material than in this specific edition. A dense, dense read unless you're intimately familiar with Greek/Persian history going in, but its place in the canon of Western literature is pivotal, and for what it is and when it came out, it is an exceptional achievement. Herodotus's attention to detail and his detailed descriptions of events, peoples and places are invaluable, even if some of his claims clearly don't stand the test of time.